chore: oxfmt whole repo (clear pre-existing format drift)

pre-push format:check was blocking on 31 files with pre-existing oxfmt
drift across CONTRIBUTING.md, docs/, manifests/, scripts/, and several
older src/ and tests/ files. None of these were touched this session;
the drift predates v0.1.9.

Applied `bun run format` (oxfmt) to bring everything up to current
format standards. No src changes, no behavioral changes.

Verification:
- bun run format:check: all matched files use the correct format
- bun run lint: 0 warnings, 0 errors
- bun run typecheck: clean
- bun run test: 80 files / 1369 tests pass + 5 skipped