Implement watch-event feature (017) with bookmark in RsvpBar

Add client-side watch/bookmark functionality: users can save events to localStorage without RSVPing via a bookmark button next to the "I'm attending" CTA. Watched events appear in the event list with a "Watching" label. Bookmark is only visible for visitors (not attendees or organizers). Includes spec, plan, research, tasks, unit tests, and E2E tests. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-03-12 22:20:57 +01:00
parent e01d5ee642
commit c450849e4d
22 changed files with 1266 additions and 31 deletions
--- a/specs/017-watch-event/data-model.md
+++ b/specs/017-watch-event/data-model.md
@@ -0,0 +1,61 @@
+# Data Model: Watch Event
+
+**Feature**: 017-watch-event
+**Date**: 2026-03-12
+
+## Entities
+
+### StoredEvent (existing — localStorage)
+
+No schema change. The existing `StoredEvent` interface already supports the watcher state:
+
+```
+StoredEvent {
+  eventToken: string        # Required — event identifier
+  organizerToken?: string   # Present → organizer role
+  title: string             # Required — display in event list
+  dateTime: string          # Required — grouping/sorting
+  rsvpToken?: string        # Present → attendee role
+  rsvpName?: string         # Present with rsvpToken
+}
+```
+
+**Watcher state**: A `StoredEvent` with only `eventToken`, `title`, and `dateTime` populated (no `organizerToken`, no `rsvpToken`). This state already occurs naturally after RSVP cancellation.
+
+## Role Hierarchy
+
+```
+organizerToken present  →  "Organizer"  (highest precedence)
+rsvpToken present       →  "Attendee"
+neither present         →  "Watching"   (new label, lowest precedence)
+```
+
+## State Transitions
+
+```
+                    ┌──────────────┐
+         watch()    │              │   un-watch()
+  (not stored) ───► │   Watching   │ ───► (not stored)
+                    │              │
+                    └──────┬───────┘
+                           │ RSVP
+                           ▼
+                    ┌──────────────┐
+                    │              │
+                    │  Attending   │
+                    │              │
+                    └──────┬───────┘
+                           │ Cancel RSVP
+                           ▼
+                    ┌──────────────┐
+                    │              │   un-watch()
+                    │   Watching   │ ───► (not stored)
+                    │              │
+                    └──────────────┘
+```
+
+Note: Organizer state is set at event creation and cannot be removed through this feature. The bookmark icon is non-interactive for organizers.
+
+## No Backend Changes
+
+This feature does not introduce any new database entities, API endpoints, or server-side logic. All data is stored in the browser's localStorage.