Concurrent SSE and API requests for the same projectId both missed the
cache (storeCache.set ran after await store.watch()), creating independent
TaskStore instances with separate EventEmitters. SSE listeners attached
to one instance while mutations fired on the other, so no events reached
the browser.
Fix: add a pendingCreations promise map that deduplicates concurrent
calls, ensuring all callers share the same in-flight promise and thus
the same store instance. Also clear pendingCreations in evictProjectStore
and evictAllProjectStores. Adds a concurrent-call regression test.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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