fix: stabilize e2e test suite and auth configuration

- Standardized E2E base URL to 127.0.0.1 to resolve cookie domain 401 errors
- Updated playwright config to strictly exclude security tests from main shards
- Refactored waitForModal helper to prevent strict mode violations on complex modals
- Fixed leak of crowdsec diagnostics tests into standard chromium project

tests/security/security-dashboard.spec.ts

@@ -133,7 +133,7 @@ test.describe('Security Dashboard @security', () => {
 
       // Create authenticated request context for cleanup (cannot reuse fixture from beforeAll)
       const cleanupRequest = await request.newContext({
-        baseURL: 'http://localhost:8080',
+        baseURL: process.env.PLAYWRIGHT_BASE_URL || 'http://127.0.0.1:8080',
         storageState: STORAGE_STATE,
       });