Add Atlas InfoSec action plans integration

Integrate Atlas InfoSec API to manage compliance action plans directly from
the ReportingPage. Users can view, create, and update action plans for host
findings without switching to the Atlas web tool.

Backend:
- Add atlasApi.js helper with Basic Auth, TLS skip, GET/PUT/PATCH/POST
- Add atlas_action_plans_cache migration for SQLite cache table
- Add atlas.js router with sync, status, and proxy CRUD endpoints
- Mount Atlas router at /api/atlas in server.js
- Extract hostId from Ivanti host findings during sync

Frontend:
- Add AtlasBadge component (amber=needs plan, green=has plan)
- Add AtlasSlideOutPanel with plan list, create form, edit capability
- Separate active plans from inactive history in collapsible section
- Custom dark-themed plan type dropdown
- Optimistic local state shows pending plans immediately after creation
- Atlas sync button on ReportingPage toolbar
- Prepopulate finding ID in create form from clicked row

Environment:
- Add ATLAS_API_URL, ATLAS_API_USER, ATLAS_API_PASS, ATLAS_SKIP_TLS to .env.example

.kiro/specs/atlas-action-plans/.config.kiro

@@ -0,0 +1 @@
+{"specId": "aa138cae-9fbf-47bf-9dc3-1169456f5706", "workflowType": "requirements-first", "specType": "feature"}