Test: Raise backend + frontend unit-test coverage

[prem22k]

Coverage is thin and uneven. Current state (this session):

• Backend: 12 test files (~45 tests) covering security/webhook/encryption paths, but core routes like projectRoutes.js, userRoutes.js, uploadRoutes.js have little or no direct coverage.
• Frontend: only 2 vitest files (26 tests) after wiring Vitest; most components are untested.
• CI uses jest --passWithNoTests (root) which masks zero-test suites.

Work needed:

• Remove --passWithNoTests so empty suites fail CI
• Add coverage thresholds (e.g. jest --coverage --coverageThreshold) for the backend security-critical paths
• Add unit tests for projectRoutes quota gate (usageService), upload auth, collaborator route
• Add a few frontend component smoke tests (ArchitectureMap, Dashboard)

Why: the 3 backend test failures found this session were only caught because CI ran them; higher coverage prevents regressions.