feat(05-08): SettingsSheet (master toggle D-09) + AppNav avatar promoted to button

- Create SettingsSheet.tsx: bottom sheet (role=dialog, z:301, Escape+backdrop-close)
  with FamilySync Notifications toggle (role=switch, aria-checked, 44px target)
  wired to usePushSubscription setEnabled + permission state
  and inline permission-denied hint (AlertCircle + 'How to enable') when denied
- Promote PhoneNav avatar div to button with onOpenSettings onClick + aria-label
- Add onOpenSettings prop to DesktopNav; add avatar button at sidebar bottom
- Thread onOpenSettings through AppNavProps
- Add @keyframes spin to tokens.css (fixes missing keyframe used by SettingsSheet + SyncStateToast)

apps/pwa/src/components/AppNav.tsx

@@ -19,25 +19,42 @@ interface AppNavProps {
   members?: LegendMember[]
   currentUserColor?: string
   currentUserName?: string
+  /** Called when the user avatar is tapped — opens the Settings sheet. */
+  onOpenSettings?: () => void
 }
 
-export function AppNav({ members = [], currentUserColor, currentUserName }: AppNavProps) {
+export function AppNav({ members = [], currentUserColor, currentUserName, onOpenSettings }: AppNavProps) {
   const isMobile = typeof window !== 'undefined' && window.matchMedia('(max-width: 767px)').matches
 
   if (isMobile) {
-    return <PhoneNav currentUserColor={currentUserColor} currentUserName={currentUserName} />
+    return (
+      <PhoneNav
+        currentUserColor={currentUserColor}
+        currentUserName={currentUserName}
+        onOpenSettings={onOpenSettings}
+      />
+    )
   }
 
-  return <DesktopNav members={members} />
+  return (
+    <DesktopNav
+      members={members}
+      currentUserColor={currentUserColor}
+      currentUserName={currentUserName}
+      onOpenSettings={onOpenSettings}
+    />
+  )
 }
 
 /** Phone: 48px top bar — app name left, user avatar right */
 function PhoneNav({
   currentUserColor,
   currentUserName,
+  onOpenSettings,
 }: {
   currentUserColor?: string
   currentUserName?: string
+  onOpenSettings?: () => void
 }) {
   const displayName = currentUserName ?? 'User'
   const color = currentUserColor ?? 'var(--color-member-0)'
@@ -69,43 +86,50 @@ function PhoneNav({
         FamilySync
       </span>
 
-      {/* User color avatar — aria-label + title per reviewer note */}
+      {/* User avatar — promoted to button to open Settings sheet (D-09) */}
-      <div
+      <button
+        onClick={onOpenSettings}
+        aria-label={`${displayName} — open settings`}
         style={{
-          width: '32px',
+          background: 'none',
-          height: '32px',
+          border: 'none',
-          borderRadius: '50%',
+          cursor: onOpenSettings ? 'pointer' : 'default',
-          background: color,
+          minWidth: '44px',
+          minHeight: '44px',
           display: 'flex',
           alignItems: 'center',
           justifyContent: 'center',
+          padding: 0,
+          borderRadius: 'var(--space-1, 4px)',
           flexShrink: 0,
-          cursor: 'default',
-          // Ensure 44px tap area with padding
-          minWidth: '44px',
-          minHeight: '44px',
-          padding: '6px',
-          boxSizing: 'border-box',
         }}
-        aria-label={displayName}
-        title={displayName}
-        role="img"
       >
         <div
           style={{
-            width: '100%',
+            width: '32px',
-            height: '100%',
+            height: '32px',
             borderRadius: '50%',
             background: color,
           }}
+          aria-hidden="true"
         />
-      </div>
+      </button>
     </header>
   )
 }
 
-/** Tablet/Desktop: 240px left sidebar — app name + nav links + color legend */
+/** Tablet/Desktop: 240px left sidebar — app name + nav links + color legend + avatar */
-function DesktopNav({ members }: { members: LegendMember[] }) {
+function DesktopNav({
+  members,
+  currentUserColor,
+  currentUserName,
+  onOpenSettings,
+}: {
+  members: LegendMember[]
+  currentUserColor?: string
+  currentUserName?: string
+  onOpenSettings?: () => void
+}) {
   const navLinkStyle = ({ isActive }: { isActive: boolean }): React.CSSProperties => ({
     display: 'flex',
     alignItems: 'center',
@@ -183,6 +207,50 @@ function DesktopNav({ members }: { members: LegendMember[] }) {
         Calendars
       </div>
       <ColorLegend members={members} />
+
+      {/* User avatar — at bottom of sidebar, opens Settings sheet (D-09) */}
+      <div style={{ marginTop: 'auto', paddingTop: 'var(--space-6)' }}>
+        <button
+          onClick={onOpenSettings}
+          aria-label={`${currentUserName ?? 'User'} — open settings`}
+          style={{
+            background: 'none',
+            border: 'none',
+            cursor: onOpenSettings ? 'pointer' : 'default',
+            minWidth: '44px',
+            minHeight: '44px',
+            display: 'flex',
+            alignItems: 'center',
+            gap: 'var(--space-3, 12px)',
+            padding: 'var(--space-2) var(--space-3, 12px)',
+            borderRadius: 'var(--space-1, 4px)',
+            width: '100%',
+            textAlign: 'left',
+          }}
+        >
+          <div
+            style={{
+              width: '32px',
+              height: '32px',
+              borderRadius: '50%',
+              background: currentUserColor ?? 'var(--color-member-0)',
+              flexShrink: 0,
+            }}
+            aria-hidden="true"
+          />
+          <span
+            style={{
+              fontSize: 'var(--text-body-size, 15px)',
+              color: 'var(--color-text-primary)',
+              overflow: 'hidden',
+              textOverflow: 'ellipsis',
+              whiteSpace: 'nowrap',
+            }}
+          >
+            {currentUserName ?? 'User'}
+          </span>
+        </button>
+      </div>
     </nav>
   )
 }

apps/pwa/src/components/SettingsSheet.tsx

@@ -0,0 +1,344 @@
+/**
+ * SettingsSheet — master notifications toggle (D-09).
+ *
+ * A bottom sheet opened by tapping the user avatar in AppNav.
+ * Contains a single master on/off toggle for all FamilySync push notifications.
+ *
+ * UI-SPEC §Surface 2:
+ *   - Bottom sheet, role="dialog", aria-modal, zIndex 301 (backdrop 300)
+ *   - Heading "Settings" + X close button
+ *   - Section label "Notifications" (uppercase, muted)
+ *   - Bell icon + toggle row
+ *   - Permission-denied hint when Notification.permission === 'denied'
+ *
+ * Toggle behavior:
+ *   on → off: DELETE subscription + localStorage.notificationsEnabled='0'
+ *   off → on (permission granted): silently subscribe (no OS dialog)
+ *   off → on (permission default): triggers tap-gated subscribe() (OS dialog)
+ *   off → on (permission denied): no-op, shows permission-denied hint inline
+ *
+ * Accessibility: role="switch", aria-checked, 44px touch targets, Escape closes.
+ * Security: T-05-24 — all copy is plain-text JSX children, no dangerouslySetInnerHTML.
+ */
+
+import { useEffect, useRef, useState } from 'react'
+import { X, Bell, AlertCircle, Loader2 } from 'lucide-react'
+import { usePushSubscription } from '../hooks/usePushSubscription.js'
+
+interface SettingsSheetProps {
+  isOpen: boolean
+  onClose: () => void
+}
+
+export function SettingsSheet({ isOpen, onClose }: SettingsSheetProps) {
+  const { subscribe, permission, isSubscribed, setEnabled } = usePushSubscription()
+  const [isTogglingOn, setIsTogglingOn] = useState(false)
+  const closeButtonRef = useRef<HTMLButtonElement>(null)
+
+  // Compute initial toggle on/off state per UI-SPEC toggle initial state rule:
+  // on when notificationsEnabled !== '0' AND permission === 'granted' AND isSubscribed
+  const isOn = permission === 'granted' && isSubscribed
+
+  // Escape key listener (CreateListSheet pattern)
+  useEffect(() => {
+    if (!isOpen) return
+    const onKeyDown = (e: KeyboardEvent) => {
+      if (e.key === 'Escape') onClose()
+    }
+    document.addEventListener('keydown', onKeyDown)
+    return () => document.removeEventListener('keydown', onKeyDown)
+  }, [isOpen, onClose])
+
+  // Focus close button on open (a11y)
+  useEffect(() => {
+    if (isOpen && closeButtonRef.current) {
+      closeButtonRef.current.focus()
+    }
+  }, [isOpen])
+
+  if (!isOpen) return null
+
+  const handleToggle = async () => {
+    if (permission === 'denied') return // no-op — show hint below
+
+    if (isOn) {
+      // on → off: unsubscribe
+      await setEnabled(false)
+    } else if (permission === 'granted') {
+      // off → on, permission already granted: silent subscribe
+      setIsTogglingOn(true)
+      try {
+        await setEnabled(true)
+      } finally {
+        setIsTogglingOn(false)
+      }
+    } else {
+      // off → on, permission 'default': needs tap-gated subscribe with OS dialog
+      // The toggle click IS the tap gesture — call subscribe() directly here.
+      setIsTogglingOn(true)
+      try {
+        const registration = await navigator.serviceWorker?.ready
+        if (registration) {
+          await subscribe(registration)
+        }
+      } catch {
+        // Permission denied by OS or error — permission state will update reactively
+      } finally {
+        setIsTogglingOn(false)
+      }
+    }
+  }
+
+  const isDisabled = permission === 'denied'
+
+  return (
+    <>
+      {/* Backdrop */}
+      <div
+        onClick={onClose}
+        aria-hidden="true"
+        style={{
+          position: 'fixed',
+          inset: 0,
+          background: 'var(--color-overlay, rgba(0,0,0,0.32))',
+          zIndex: 300,
+        }}
+      />
+
+      {/* Sheet */}
+      <div
+        role="dialog"
+        aria-modal="true"
+        aria-label="Settings"
+        style={{
+          position: 'fixed',
+          bottom: 0,
+          left: 0,
+          right: 0,
+          background: 'var(--color-surface-raised, #ffffff)',
+          borderRadius: '12px 12px 0 0',
+          boxShadow: '0 -4px 24px rgba(0,0,0,0.15)',
+          padding: 'var(--space-6, 24px)',
+          zIndex: 301,
+          fontFamily: 'var(--font-family-base, system-ui, sans-serif)',
+          maxWidth: '480px',
+          margin: '0 auto',
+        }}
+      >
+        {/* Heading row */}
+        <div
+          style={{
+            display: 'flex',
+            alignItems: 'center',
+            justifyContent: 'space-between',
+            marginBottom: 'var(--space-6, 24px)',
+          }}
+        >
+          <h2
+            style={{
+              margin: 0,
+              fontSize: 'var(--text-heading-size, 18px)',
+              fontWeight: 600,
+              lineHeight: 'var(--text-heading-line-height, 1.25)',
+              color: 'var(--color-text-primary, #111318)',
+            }}
+          >
+            Settings
+          </h2>
+          <button
+            ref={closeButtonRef}
+            onClick={onClose}
+            aria-label="Close settings"
+            style={{
+              background: 'none',
+              border: 'none',
+              cursor: 'pointer',
+              minWidth: '44px',
+              minHeight: '44px',
+              display: 'flex',
+              alignItems: 'center',
+              justifyContent: 'center',
+              color: 'var(--color-text-secondary, #5c6472)',
+              borderRadius: 'var(--space-1, 4px)',
+            }}
+          >
+            <X size={20} aria-hidden="true" />
+          </button>
+        </div>
+
+        {/* Section label */}
+        <div
+          style={{
+            fontSize: 'var(--text-label-size, 13px)',
+            fontWeight: 600,
+            color: 'var(--color-text-muted, #9CA3AF)',
+            textTransform: 'uppercase',
+            letterSpacing: '0.06em',
+            marginBottom: 'var(--space-2, 8px)',
+          }}
+        >
+          Notifications
+        </div>
+
+        {/* Toggle row */}
+        <div
+          style={{
+            display: 'flex',
+            alignItems: 'center',
+            gap: 'var(--space-3, 12px)',
+            padding: 'var(--space-2, 8px) 0',
+          }}
+        >
+          <Bell
+            size={20}
+            aria-hidden="true"
+            style={{
+              color: 'var(--color-text-secondary, #5c6472)',
+              flexShrink: 0,
+            }}
+          />
+
+          {/* Label column */}
+          <div style={{ flex: 1, minWidth: 0 }}>
+            <div
+              style={{
+                fontSize: 'var(--text-body-size, 15px)',
+                fontWeight: 400,
+                color: 'var(--color-text-primary, #111318)',
+                lineHeight: 1.4,
+              }}
+            >
+              FamilySync Notifications
+            </div>
+            <div
+              style={{
+                fontSize: 'var(--text-label-size, 13px)',
+                color: 'var(--color-text-secondary, #5c6472)',
+                lineHeight: 1.4,
+                marginTop: '2px',
+              }}
+            >
+              Reminders, event changes, list updates
+            </div>
+          </div>
+
+          {/* Toggle switch or spinner */}
+          {isTogglingOn ? (
+            <Loader2
+              size={20}
+              aria-hidden="true"
+              style={{
+                color: 'var(--color-text-secondary, #5c6472)',
+                animation: 'spin 1s linear infinite',
+                flexShrink: 0,
+              }}
+            />
+          ) : (
+            <button
+              role="switch"
+              aria-checked={isOn}
+              aria-label={isOn ? 'FamilySync Notifications, on' : 'FamilySync Notifications, off'}
+              onClick={() => { void handleToggle() }}
+              disabled={isDisabled}
+              style={{
+                // 44px touch target
+                minWidth: '44px',
+                minHeight: '44px',
+                display: 'flex',
+                alignItems: 'center',
+                justifyContent: 'center',
+                background: 'none',
+                border: 'none',
+                cursor: isDisabled ? 'default' : 'pointer',
+                padding: 0,
+                flexShrink: 0,
+                opacity: isDisabled ? 0.5 : 1,
+              }}
+            >
+              {/* Toggle track */}
+              <div
+                style={{
+                  width: '44px',
+                  height: '24px',
+                  borderRadius: '12px',
+                  background: isOn
+                    ? 'var(--color-member-0, #4A90D9)'
+                    : 'var(--color-border, #E2E4E9)',
+                  position: 'relative',
+                  transition: 'background 0.15s ease',
+                  pointerEvents: 'none',
+                }}
+              >
+                {/* Toggle thumb */}
+                <div
+                  style={{
+                    position: 'absolute',
+                    top: '2px',
+                    left: isOn ? '22px' : '2px',
+                    width: '20px',
+                    height: '20px',
+                    borderRadius: '50%',
+                    background: '#ffffff',
+                    boxShadow: '0 1px 3px rgba(0,0,0,0.2)',
+                    transition: 'left 0.15s ease',
+                  }}
+                />
+              </div>
+            </button>
+          )}
+        </div>
+
+        {/* Permission-denied hint — only when OS permission === 'denied' */}
+        {permission === 'denied' && (
+          <div
+            style={{
+              display: 'flex',
+              alignItems: 'flex-start',
+              gap: 'var(--space-2, 8px)',
+              marginTop: 'var(--space-2, 8px)',
+              padding: 'var(--space-3, 12px)',
+              background: 'var(--color-surface-dim, #F7F7F8)',
+              borderRadius: 'var(--space-1, 4px)',
+            }}
+          >
+            <AlertCircle
+              size={16}
+              aria-hidden="true"
+              style={{
+                color: 'var(--color-destructive, #DC2626)',
+                flexShrink: 0,
+                marginTop: '1px',
+              }}
+            />
+            <div>
+              <span
+                style={{
+                  fontSize: 'var(--text-label-size, 13px)',
+                  color: 'var(--color-text-secondary, #5c6472)',
+                  lineHeight: 1.4,
+                }}
+              >
+                Notifications are blocked in your browser settings.{' '}
+              </span>
+              <button
+                onClick={onClose}
+                style={{
+                  background: 'none',
+                  border: 'none',
+                  padding: 0,
+                  cursor: 'pointer',
+                  fontSize: 'var(--text-label-size, 13px)',
+                  color: 'var(--color-focus-ring, #4A90D9)',
+                  textDecoration: 'underline',
+                  fontFamily: 'inherit',
+                }}
+              >
+                How to enable
+              </button>
+            </div>
+          </div>
+        )}
+      </div>
+    </>
+  )
+}

apps/pwa/src/styles/tokens.css

@@ -136,3 +136,12 @@
     background-position: 200% 0;
   }
 }
+
+@keyframes spin {
+  from {
+    transform: rotate(0deg);
+  }
+  to {
+    transform: rotate(360deg);
+  }
+}