docs: contributor onboarding path and CODEOWNERS #292

Job	Run time
Performance benchmarks (gated)	34s
Verify prod requirements.txt is sufficient	9s
mypy	20s
pytest (macos-latest)	44s
Frontend unit tests (vitest) (ubuntu-latest)	26s
API integration tests + coverage (windows-latest)	51s
API integration tests + coverage (ubuntu-latest)	29s
pytest (windows-latest)	1m 26s
ruff + pip-audit (ubuntu-latest)	23s
Frontend unit tests (vitest) (macos-latest)	38s
Frontend unit tests (vitest) (windows-latest)	1m 26s
ruff + pip-audit (windows-latest)	1m 12s
API integration tests + coverage (macos-latest)	36s
pytest (ubuntu-latest)	46s
ruff + pip-audit (macos-latest)	23s
	10m 23s

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