Implement task status workflow: claimed, in-progress, completed

Added granular task state management to scheduled events/tasks with three states plus unclaimed. Tasks now support a full workflow from claiming to completion with visual feedback at each stage.

**New Task States:**
- **Unclaimed** (no RSVP event) - Task available for anyone to claim
- **Claimed** - User has reserved the task but hasn't started
- **In Progress** - User is actively working on the task
- **Completed** - Task is done
- **Blocked** - Task is stuck (supported but not yet used in UI)
- **Cancelled** - Task won't be completed (supported but not yet used in UI)

**Service Layer (ScheduledEventService.ts):**
- Updated `EventCompletion` interface: replaced `completed: boolean` with `taskStatus: TaskStatus`
- Added `TaskStatus` type: `'claimed' | 'in-progress' | 'completed' | 'blocked' | 'cancelled'`
- New methods: `claimTask()`, `startTask()`, `getTaskStatus()`
- Refactored `completeEvent()` and renamed `uncompleteEvent()` to `unclaimTask()`
- Internal `updateTaskStatus()` method handles all state changes
- Uses `task-status` tag instead of `completed` tag in Nostr events
- `unclaimTask()` publishes deletion event (kind 5) to remove RSVP
- Backward compatibility: reads old `completed` tag and converts to new taskStatus

**Composable (useScheduledEvents.ts):**
- Exported new methods: `claimTask`, `startTask`, `unclaimTask`, `getTaskStatus`
- Updated `completeEvent` signature to accept occurrence parameter
- Marked `toggleComplete` as deprecated (still works for compatibility)

**UI (ScheduledEventCard.vue):**
- Context-aware action buttons based on current task status:
  - Unclaimed: "Claim Task" button
  - Claimed: "Start Task" + "Unclaim" buttons
  - In Progress: "Mark Complete" + "Unclaim" buttons
  - Completed: "Unclaim" button only
- Status badges with icons and color coding:
  - 👋 Claimed (blue)
  - 🔄 In Progress (orange)
  - ✓ Completed (green)
- Shows who claimed/is working on/completed each task
- Unified confirmation dialog for all actions
- Quick action buttons in collapsed view
- Full button set in expanded view

**Feed Integration (NostrFeed.vue):**
- Added handlers: `onClaimTask`, `onStartTask`, `onCompleteTask`, `onUnclaimTask`
- Passes `getTaskStatus` prop to ScheduledEventCard
- Wired up all new event emitters

**Nostr Protocol:**
- Uses NIP-52 Calendar Event RSVP (kind 31925)
- Custom `task-status` tag for granular state tracking
- Deletion events (kind 5) for unclaiming tasks
- Fully decentralized - all state stored on Nostr relays

🐢 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/modules/nostr-feed/components/NostrFeed.vue

@@ -99,7 +99,16 @@ const { getDisplayName, fetchProfiles } = useProfiles()
 const { getEventReactions, subscribeToReactions, toggleLike } = useReactions()
 
 // Use scheduled events service
-const { getEventsForSpecificDate, getCompletion, toggleComplete, allCompletions } = useScheduledEvents()
+const {
+  getEventsForSpecificDate,
+  getCompletion,
+  getTaskStatus,
+  claimTask,
+  startTask,
+  completeEvent,
+  unclaimTask,
+  allCompletions
+} = useScheduledEvents()
 
 // Selected date for viewing scheduled tasks (defaults to today)
 const selectedDate = ref(new Date().toISOString().split('T')[0])
@@ -255,14 +264,40 @@ async function onToggleLike(note: FeedPost) {
   }
 }
 
-// Handle scheduled event completion toggle
-async function onToggleComplete(event: ScheduledEvent, occurrence?: string) {
-  console.log('🎯 NostrFeed: onToggleComplete called for event:', event.title, 'occurrence:', occurrence)
+// Task action handlers
+async function onClaimTask(event: ScheduledEvent, occurrence?: string) {
+  console.log('👋 NostrFeed: Claiming task:', event.title)
   try {
-    await toggleComplete(event, occurrence)
-    console.log('✅ NostrFeed: toggleComplete succeeded')
+    await claimTask(event, '', occurrence)
   } catch (error) {
-    console.error('❌ NostrFeed: Failed to toggle event completion:', error)
+    console.error('❌ Failed to claim task:', error)
+  }
+}
+
+async function onStartTask(event: ScheduledEvent, occurrence?: string) {
+  console.log('▶️ NostrFeed: Starting task:', event.title)
+  try {
+    await startTask(event, '', occurrence)
+  } catch (error) {
+    console.error('❌ Failed to start task:', error)
+  }
+}
+
+async function onCompleteTask(event: ScheduledEvent, occurrence?: string) {
+  console.log('✅ NostrFeed: Completing task:', event.title)
+  try {
+    await completeEvent(event, occurrence, '')
+  } catch (error) {
+    console.error('❌ Failed to complete task:', error)
+  }
+}
+
+async function onUnclaimTask(event: ScheduledEvent, occurrence?: string) {
+  console.log('🔙 NostrFeed: Unclaiming task:', event.title)
+  try {
+    await unclaimTask(event, occurrence)
+  } catch (error) {
+    console.error('❌ Failed to unclaim task:', error)
   }
 }
 
@@ -514,8 +549,12 @@ function cancelDelete() {
               :event="event"
               :get-display-name="getDisplayName"
               :get-completion="getCompletion"
+              :get-task-status="getTaskStatus"
               :admin-pubkeys="adminPubkeys"
-              @toggle-complete="onToggleComplete"
+              @claim-task="onClaimTask"
+              @start-task="onStartTask"
+              @complete-task="onCompleteTask"
+              @unclaim-task="onUnclaimTask"
             />
           </div>
           <div v-else class="text-center py-3 text-muted-foreground text-sm px-4">