Use session IDs for scratches and queued messages (Vibe Kanban) (#1613)

* All changes have been completed. Here's a summary of what was done:

## Summary

Changed both scratches and queued messages to use session IDs instead of workspace IDs:

### Files Modified

1. **`frontend/src/components/tasks/TaskFollowUpSection.tsx`**
   - Changed `useScratch(ScratchType.DRAFT_FOLLOW_UP, workspaceId ?? '')` → `useScratch(ScratchType.DRAFT_FOLLOW_UP, sessionId ?? '')`

2. **`crates/server/src/routes/sessions/queue.rs`**
   - Changed `session.workspace_id` → `session.id` in all three queue operations (queue, cancel, get status)

3. **`crates/services/src/services/queued_message.rs`**
   - Renamed `task_attempt_id` → `session_id` in `QueuedMessage` struct
   - Updated all method parameters and comments

4. **`crates/local-deployment/src/container.rs`**
   - Changed `ctx.workspace.id` → `ctx.session.id` for queue lookups and scratch deletion
   - Updated log messages to reference "session" instead of "workspace"

5. **`shared/types.ts`** (auto-generated)
   - `QueuedMessage.task_attempt_id` → `QueuedMessage.session_id`

* Cleanup script changes for task attempt 4df90bcd-f261-41ca-bac3-8f7c2fc576c5

* Build passes. The fix has been applied. Found and fixed one missed instance in `sessions/mod.rs` where `Scratch::delete` was using `workspace.id` instead of `session.id`.

frontend/src/components/tasks/TaskFollowUpSection.tsx

@@ -133,7 +133,7 @@ export function TaskFollowUpSection({
     scratch,
     updateScratch,
     isLoading: isScratchLoading,
-  } = useScratch(ScratchType.DRAFT_FOLLOW_UP, workspaceId ?? '');
+  } = useScratch(ScratchType.DRAFT_FOLLOW_UP, sessionId ?? '');
 
   // Derive the message and variant from scratch
   const scratchData: DraftFollowUpData | undefined =