feat: add PolicyPackSelectorComponent with tests and integration

- Implemented PolicyPackSelectorComponent for selecting policy packs.
- Added unit tests for component behavior, including API success and error handling.
- Introduced monaco-workers type declarations for editor workers.
- Created acceptance tests for guardrails with stubs for AT1–AT10.
- Established SCA Failure Catalogue Fixtures for regression testing.
- Developed plugin determinism harness with stubs for PL1–PL10.
- Added scripts for evidence upload and verification processes.

src/Web/StellaOps.Web/package.json

@@ -31,8 +31,10 @@
     "@angular/platform-browser": "^17.3.0",
     "@angular/platform-browser-dynamic": "^17.3.0",
     "@angular/router": "^17.3.0",
+    "monaco-editor": "0.52.0",
     "rxjs": "~7.8.0",
     "tslib": "^2.3.0",
+    "yaml": "^2.4.2",
     "zone.js": "~0.14.3"
   },
   "devDependencies": {