chore: bump version to v1.5.2

v1.5.2 — StateService single source of truth, search pipeline fixes,
backend loading overlay.

Key changes:
- StateService as sole persistence layer (session delete/switch/persist)
- Shutdown flush via Electron before-quit + POST /api/state/flush
- Large data (jobCards, searchHistory) written to disk files, not HTTP
- Pipeline: JD fetch failure ≠ AI failure, no false ABORT
- Indeed dedup: title+company dual strategy for pagead/clk URLs
- Search tool build: require logged-in browser, feed JD errors to AI
- verify-jd: 50% success threshold, failure feedback to AI regeneration
- Phase 2 prompt: humanClick + URL check + failure reason markers
- Backend loading overlay: wait for ALL services before UI interaction
- Comprehensive /api/readiness endpoint (server+WS+dbservice+toolService)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: amingclawdev

package.json

@@ -1,7 +1,7 @@
 {
   "name": "web3toolbox",
   "author": "Aming",
-  "version": "1.5.1",
+  "version": "1.5.2",
   "private": true,
   "main": "electron.js",
   "license": "MIT",