Fix 5 wrong API endpoints + stop swallowing JS errors in E2E

Endpoint fixes:
- AuditLog: /api/audit-logs → /api/audit-log
- BugTracker: /api/bugs → /api/bug-reports, create → /api/bug-report
- BugTracker: fix create body (content+priority, not title/description)
- MyDiary: /api/brand-settings → /api/brand
- MyDiary: /api/me/display-name → PUT /api/me
- RecipeSearch: /api/category-modules → /api/categories

Test improvements:
- Remove blanket uncaught:exception swallow (only ignore ResizeObserver)
- Add endpoint-parity.cy.js: intercept-based test that verifies correct
  API endpoints are called and wrong ones are NOT called

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

frontend/cypress/support/e2e.js

@@ -1,5 +1,11 @@
-// Ignore uncaught exceptions from the app (API errors during loading, etc.)
-Cypress.on('uncaught:exception', () => false)
+// Log uncaught exceptions but don't swallow them blindly.
+// Only ignore known non-critical errors (e.g. ResizeObserver).
+Cypress.on('uncaught:exception', (err) => {
+  // ResizeObserver loop errors are harmless
+  if (err.message.includes('ResizeObserver')) return false
+  // Let all other errors fail the test
+  return true
+})
 
 // Custom commands for the oil calculator app