fix: self-healing claimNextMessage prevents stuck processing messages (#1159)

* fix: self-healing claimNextMessage prevents stuck processing messages

claimAndDelete → claimNextMessage with atomic self-healing: resets stale
processing messages (>60s) back to pending before claiming. Eliminates
stuck messages from generator crashes without external timers. Removes
redundant idle-timeout reset in worker-service.ts. Adds QUEUE to logger
Component type.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix: update stale comments in SessionQueueProcessor to reflect claim-confirm pattern

Comments still referenced the old claim-and-delete pattern after the
claimNextMessage rename. Updated to accurately describe the current
lifecycle where messages are marked as processing and stay in DB until
confirmProcessed() is called.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix: move Date.now() inside transaction and extract stale threshold constant

- Move Date.now() inside claimNextMessage transaction closure so timestamp
  is fresh if WAL contention causes retry
- Extract STALE_PROCESSING_THRESHOLD_MS to module-level constant
- Add comment clarifying strict < boundary semantics

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

src/utils/logger.ts

@@ -15,7 +15,7 @@ export enum LogLevel {
   SILENT = 4
 }
 
-export type Component = 'HOOK' | 'WORKER' | 'SDK' | 'PARSER' | 'DB' | 'SYSTEM' | 'HTTP' | 'SESSION' | 'CHROMA' | 'CHROMA_SYNC' | 'FOLDER_INDEX' | 'CLAUDE_MD';
+export type Component = 'HOOK' | 'WORKER' | 'SDK' | 'PARSER' | 'DB' | 'SYSTEM' | 'HTTP' | 'SESSION' | 'CHROMA' | 'CHROMA_SYNC' | 'FOLDER_INDEX' | 'CLAUDE_MD' | 'QUEUE';
 
 interface LogContext {
   sessionId?: number;