a215cd3 fix(billing): cap metering batch size to 500
6ecd72a test(integration): api contract tests against fixtures
c4ddbd2 fix(utils): logger drops circular references safely
3d51ee1 feat(billing): credit notes for refund flows
0ce7a54 chore: prettier + eslint config alignment
01a008f fix(ui): Modal scroll lock on iOS Safari
02b93f2 feat(api): conditional requests with ETag support
9bf6e8c docs(api): OpenAPI examples for error envelope
775d8e9 fix(auth): session fixation on privilege elevation
47e957f refactor(utils): consolidate validation error shapes