435ab285c1
RecoverStuckTasks scans for tasks with updated_at > 5min ago and re-enqueues them. This incorrectly matched tasks actively being processed by the worker (e.g. slow downloads), causing double-processing. Add inflight sync.Map to track taskIDs currently inside ProcessTask. RecoverStuckTasks skips tasks found in inflight. On server restart inflight is empty (in-memory), so genuinely stuck tasks are still correctly recovered. Also: increase taskCh buffer 16→10000, add periodic RecoverStuckTasks goroutine in TaskPoller (every 5min), and add status guard in ProcessTask as defense-in-depth against duplicate enqueues.