fix(dev-deps): enforce [dev] install + align docs to CI

[HumanBean17]

Problem

Agents repeatedly reported green locally, red on CI. Root cause: a one-character mismatch between CI and the docs agents follow.

• CI (.github/workflows/test.yml:69): pip install -e ".[dev]"
• Agent docs (AGENTS.md:9, docs/JAVA-CODEBASE-RAG-CLI.md:10): pip install -e . — no [dev]

pytest-asyncio lives only under the [dev] extra (pyproject.toml:53). An agent following the doc got a venv with no pytest-asyncio. pytest.ini sets asyncio_mode = auto, which is a silent no-op without the plugin — so every async def test_* was collected and failed instantly (~0.01s, coroutine-never-awaited) instead of running.

That fast-failure signature broke reasoning twice:

1. The real regression looked identical to the env-induced async failures.
2. The "baseline on master" ran in the same broken venv → same fake failures → a false "pre-existing on master" conclusion. Two wrongs cancelled out and masked a real create_index regression.

A worktree would not have prevented this — the repo-root .venv is shared across worktrees. The fix has to be env-health verification.

Fix

1. Align docs to CI — AGENTS.md:9 and docs/JAVA-CODEBASE-RAG-CLI.md:10 now say -e ".[dev]" (matching CI and README.md:274).
2. Fail loud, not silent (tests/conftest.py) — new _enforce_dev_deps(), wired into pytest_configure ahead of the existing _enforce_editable_install() guard and mirroring its style: missing pytest-asyncio now exits with returncode=4 and a one-line fix command, instead of N silent 0.01s failures. Also aligned the editable-install guard's message to .[dev] so both guards print one canonical command.

Verification

• ruff check tests/conftest.py — clean (repo line-length 100).
• Guard, isolated: pytest-asyncio present → returns silently; absent (sys.modules['pytest_asyncio']=None) → raises _pytest.outcomes.Exit, returncode 4, correct message.
• In real pytest --collect-only: the [install] guard fired, not [dev-deps] → confirms the new guard runs first and does not false-positive.

Out of scope (intentionally left)

• tests/test_jrag_*.py assertion hints (run: pip install -e .) — about the jrag entrypoint being installed, not dev deps.
• plans/** — historical/completed records.

🤖 Generated with Claude Code