feat(17-04): wire logo img into BrandSlot, set --brand-logo-border-radius 0

- Replace placeholder FS div with decorative <img src="/logo.svg" alt="" aria-hidden>
- Apply Surface B-1 style (width/height brand-logo-size, borderRadius token, contain/block)
- Update --brand-logo-border-radius from 50% to 0 (SVG draws its own rx=104 shape)
- h1 FamilySync and tagline p unchanged; LoginPage.tsx untouched (seam contract honored)
- No dangerouslySetInnerHTML (T-05-24 invariant maintained)

apps/pwa/src/components/BrandSlot.tsx

@@ -1,24 +1,20 @@
 /**
  * BrandSlot — Phase 17 seam component for the login page brand area.
  *
- * Phase 19 ships a minimal shippable placeholder: a 48px circle with "FS"
+ * Phase 19 shipped a minimal shippable placeholder: a 48px circle with "FS"
  * initials, the app name "FamilySync", and the tagline "Family calendar & lists".
  *
- * Phase 17 replaces the internals of this component (swap the placeholder div for
+ * Phase 17 replaces the placeholder div with a decorative logo <img> — the approved
- * an <img> with a real logo) without touching LoginPage's layout. This isolates
+ * FamilySync family-house SVG. LoginPage layout is untouched (seam contract honored;
- * the branding seam — see 19-UI-SPEC.md §Brand Slot section.
+ * see 19-UI-SPEC.md §Brand Slot section).
  *
- * CSS custom properties used (all set in tokens.css with placeholder defaults;
+ * CSS custom properties used (all set in tokens.css):
- * Phase 17 overrides these values):
+ *   --brand-logo-size         — image size (default: 48px)
- *   --brand-logo-bg           — logo circle background (default: var(--color-member-0))
+ *   --brand-logo-border-radius — image border-radius (0 — SVG draws its own shape)
- *   --brand-logo-text         — initials color (default: #ffffff)
- *   --brand-logo-size         — circle diameter (default: 48px)
- *   --brand-logo-border-radius — circle shape (default: 50%)
  *
  * Accessibility:
  *   <h1> contains the app name — screen readers read "FamilySync" as the page title.
- *   The logo circle is aria-hidden (the text is the accessible label).
+ *   The logo image is decorative (alt="", aria-hidden="true").
- *   No <img> today → no broken image ref → no layout shift when Phase 17 replaces it.
  *
  * Security: all copy is plain-text JSX children — no dangerouslySetInnerHTML (T-05-24).
  */
@@ -26,28 +22,22 @@
 export function BrandSlot() {
   return (
     <div style={{ textAlign: 'center' }}>
-      {/* Phase 17 replaces this div with <img src="..." alt="" /> */}
+      {/* Decorative brand logo — Phase 17 approved brand mark (logo.svg) */}
-      <div
+      <img
+        src="/logo.svg"
+        alt=""
         aria-hidden="true"
         style={{
           width: 'var(--brand-logo-size, 48px)',
           height: 'var(--brand-logo-size, 48px)',
-          borderRadius: 'var(--brand-logo-border-radius, 50%)',
+          borderRadius: 'var(--brand-logo-border-radius)',
-          background: 'var(--brand-logo-bg, var(--color-member-0, #4a90d9))',
-          color: 'var(--brand-logo-text, #ffffff)',
-          display: 'flex',
-          alignItems: 'center',
-          justifyContent: 'center',
           margin: '0 auto var(--space-2, 8px)',
-          fontSize: 'var(--text-display-size, 24px)',
+          display: 'block',
-          fontWeight: 600,
-          fontFamily: 'var(--font-family-base)',
-          flexShrink: 0,
           aspectRatio: '1 / 1',
+          objectFit: 'contain',
+          flexShrink: 0,
         }}
-      >
+      />
-        FS
-      </div>
 
       {/* App name — <h1> so screen readers identify the page (UI-SPEC §Accessibility) */}
       <h1

apps/pwa/src/styles/tokens.css

@@ -103,7 +103,7 @@
   --brand-logo-bg: var(--color-member-0); /* placeholder circle background */
   --brand-logo-text: #ffffff; /* placeholder initials color */
   --brand-logo-size: 48px; /* reserved slot height; keep 1:1 aspect */
-  --brand-logo-border-radius: 50%; /* circle for initials; Phase 17 may change */
+  --brand-logo-border-radius: 0; /* SVG draws its own rounded-square background (rx=104); no CSS clip needed */
   --brand-app-name: 'FamilySync'; /* drives doc only — not used as CSS content */
 
   /* ─────────────────────────────────────────────────────────────────────────