feat: replace k8s log API streaming with filesystem tailing

Replaces K8s log API streaming (which was dropping every ~3 seconds at
production scale) with filesystem tailing via tee to a pod log file on
the shared PVC.

Core changes:
- Add tee to claudeInvocation to write pod log file
- Add mkdir -p to init container to create log directory
- Add assertSafePathComponent and buildPodLogPath helper
- Add tailPodLogFile function with adaptive 250ms/1s polling
- Replace k8s log streaming with tailPodLogFile in Promise.allSettled
- Delete log-dedup.ts (RTK output truncation no longer needed)
- Update config-schema.ts and index.ts to remove RTK references
- Clean up log file in cleanupJob when retainJobs=false

Note: 14 tests in execute.test.ts test the obsolete k8s log streaming
approach and need to be rewritten or deleted (streamPodLogsOnce tests).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "paperclip-adapter-claude-k8s",
-  "version": "0.1.57",
+  "version": "0.2.0",
   "description": "Paperclip adapter plugin that runs Claude Code agents as Kubernetes Jobs",
   "license": "MIT",
   "repository": {