MSW v2.7.0 fallback layer covering dashboard/users/exams/grades domains.
NEXT_PUBLIC_MSW=1 enables browser Service Worker + SSR route handler mock
responses without backend. Production build excludes all mock data via
Turbopack resolveAlias redirecting @/mocks to empty stub.
Acceptance: build bundle (client+server) verified clean of mock strings;
typecheck/lint/vitest (231 tests) all pass.
