fix(03): WR-01 preserve existing RRULE on edit instead of resetting to none

apps/api/src/broker/outboxWorker.ts

@@ -31,7 +31,7 @@ import { createFastmailClient } from './client.js'
 import { decryptPassword } from './crypto.js'
 import { syncCalendar } from './sync.js'
 import { createCalendarEvent, updateCalendarEvent, deleteCalendarEvent } from './write.js'
-import { buildVeventString, RRULE_PRESETS } from './vevent.js'
+import { buildVeventString, extractRruleString, RRULE_PRESETS } from './vevent.js'
 import type { FastmailClient } from './client.js'
 
 // ── Constants (D-07) ────────────────────────────────────────────────────────
@@ -183,16 +183,19 @@ async function dispatchRow(row: OutboxRow): Promise<DispatchResult> {
     } catch {
       return { success: false, conflict: false, hardFail: true, transient: false, error: 'payload parse failed' }
     }
-    const { icsString } = buildVeventString({
-      uid: row.uid,
-      summary: fields.title as string,
-      allDay: fields.allDay as boolean,
-      dtstart: fields.allDay ? (fields.start as string) : new Date(fields.start as string),
-      dtend: fields.allDay ? (fields.end as string) : new Date(fields.end as string),
-      location: fields.location as string | undefined,
-      description: fields.description as string | undefined,
-      rruleString: fields.recurrence && fields.recurrence !== 'none' ? RRULE_PRESETS[fields.recurrence as string] : undefined,
-    })
+    // WR-01: recurrence preservation. The PWA omits `recurrence` from an edit payload
+    // (it cannot read the existing RRULE — not in the occurrence contract, D-03), so on
+    // update we must NOT rebuild the VEVENT with no RRULE — that would silently convert a
+    // recurring series into a single event. When the payload carries no explicit
+    // recurrence, fall back to the RRULE already stored in calendarEvents.rawVevent.
+    // An explicit recurrence value (including 'none') still overrides — that is a
+    // deliberate user change. Read rawVevent in the same scoped query as the fresh etag.
+    let preservedRrule: string | undefined
+    const hasExplicitRecurrence = Object.prototype.hasOwnProperty.call(fields, 'recurrence')
+    const rruleFromPayload =
+      fields.recurrence && fields.recurrence !== 'none'
+        ? RRULE_PRESETS[fields.recurrence as string]
+        : undefined
     // WR-02: re-read the freshest etag from calendarEvents just before PUT.
     // Rapid successive edits to the same uid enqueue multiple update rows, each
     // carrying the etag at enqueue time. If a prior edit succeeded and triggered
@@ -210,7 +213,7 @@ async function dispatchRow(row: OutboxRow): Promise<DispatchResult> {
     // calendarUrl so the freshest etag belongs to the writing member.
     let etagForPut: string | null = row.etag ?? null
     const freshEtagRows = (await db
-      .select({ etag: calendarEvents.etag })
+      .select({ etag: calendarEvents.etag, rawVevent: calendarEvents.rawVevent })
       .from(calendarEvents)
       .innerJoin(calendars, eq(calendarEvents.calendarId, calendars.id))
       .where(
@@ -220,11 +223,28 @@ async function dispatchRow(row: OutboxRow): Promise<DispatchResult> {
           eq(calendars.url, row.calendarUrl),
         ),
       )
-      .limit(1)) as Array<{ etag: string | null }>
+      .limit(1)) as Array<{ etag: string | null; rawVevent: string | null }>
     if (freshEtagRows.length > 0 && freshEtagRows[0].etag != null) {
       etagForPut = freshEtagRows[0].etag
     }
 
+    // WR-01: when the edit payload carries no explicit recurrence, preserve the RRULE
+    // already on the stored event so an edit does not strip a recurring series.
+    if (!hasExplicitRecurrence && freshEtagRows.length > 0 && freshEtagRows[0].rawVevent) {
+      preservedRrule = extractRruleString(freshEtagRows[0].rawVevent)
+    }
+
+    const { icsString } = buildVeventString({
+      uid: row.uid,
+      summary: fields.title as string,
+      allDay: fields.allDay as boolean,
+      dtstart: fields.allDay ? (fields.start as string) : new Date(fields.start as string),
+      dtend: fields.allDay ? (fields.end as string) : new Date(fields.end as string),
+      location: fields.location as string | undefined,
+      description: fields.description as string | undefined,
+      rruleString: hasExplicitRecurrence ? rruleFromPayload : (preservedRrule ?? rruleFromPayload),
+    })
+
     response = await updateCalendarEvent(
       client,
       row.calendarObjectUrl,