35b1e57862
Three foot-guns in the canonical test runner, each of which cost real debugging time by making an unverified run look verified. 1. Zero collection across the whole run reported success-shaped output. Per-file rc=5 is rewritten to rc=0 so a platform-gated file (every test skipped on this OS) doesn't fail the suite — correct, but it also meant a run where NOTHING was collected anywhere printed "0 tests passed, 0 failed (100% complete)" and, with no failures recorded, could exit 0. Now the run-level guard counts every collected outcome (passed/failed/skipped/errors/xfailed/xpassed): an all-skipped file still passes, but zero-collected-anywhere prints an explicit "✗ NO TESTS RAN — this is NOT a pass" block naming the likely causes and returns 1. 2. A venv without pytest was selected merely for existing. The probe accepted any directory with bin/activate, so in a checkout/worktree without a local .venv it picked the RELEASE venv (~/.hermes/hermes-agent/venv, no pytest). Every file then died with "No module named pytest" and the run reported 0 tests. Candidates are now import-checked for pytest — the same guard the HERMES_PYTHON fallback already applied — and a skipped candidate is named on stderr. 3. Pytest node ids were silently discarded. This runner is file-granular, so `tests/foo.py::TestBar::test_baz` isn't an existing path: discovery dropped it and the run ended "No test files to run" while the selector looked accepted. Node ids are now translated to the FILE plus an inferred `-k` on the leaf name (parametrized ids reduced to the function name), with a note explaining the translation. An explicit caller `-k` wins over the inferred one. Tests: 4 behavior contracts in tests/test_run_tests_parallel.py. Verified by sabotage — reverting the runner fails 3 of the 4 (the fourth pins the pre-existing all-skipped tolerance so fix 1 can't regress it).