fix: jobs stuck in initializing state when failing before execution_start (#8689)

## Summary

Fix jobs getting permanently stuck in "initializing" state when they
fail before the `execution_start` WebSocket event fires.

## Changes

- **What**: Added `reconcileInitializingPrompts(activeJobIds)` to
`executionStore` that removes orphaned initializing prompt IDs not
present in the active jobs set. Called from `queueStore.update()` after
fetching Running/Pending jobs, ensuring stale initializing states are
cleaned up on every queue poll.

## Review Focus

- The reconciliation delegates to the existing
`clearInitializationByPromptIds` to avoid duplicating Set-diffing logic.
- Only runs during `queueStore.update()` which is already a periodic
poll — no additional network calls.

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-8689-fix-jobs-stuck-in-initializing-state-when-failing-before-execution_start-2ff6d73d3650814dbeeeda71c8bb7d43)
by [Unito](https://www.unito.io)

src/stores/queueStore.ts

@@ -537,6 +537,18 @@ export const useQueueStore = defineStore('queue', () => {
         }
       })
 
+      // Only reconcile when the queue fetch returned data. api.getQueue()
+      // returns empty Running/Pending on transient errors, which would
+      // incorrectly clear all initializing prompts.
+      const queueHasData = queue.Running.length > 0 || queue.Pending.length > 0
+      if (queueHasData) {
+        const activeJobIds = new Set([
+          ...queue.Running.map((j) => j.id),
+          ...queue.Pending.map((j) => j.id)
+        ])
+        executionStore.reconcileInitializingPrompts(activeJobIds)
+      }
+
       // Sort by create_time descending and limit to maxItems
       const sortedHistory = [...history]
         .sort((a, b) => b.create_time - a.create_time)