fix: second-pass bug sweep — crawler traversal guards, FIFO hangs, atomic writes, CLI contract #320

Job	Run time
test (ubuntu-latest)	6m 31s
test-release	17m 36s
test (windows-latest)	34m 47s
coverage-docker (nuget)	5m 8s
coverage-docker (pypi)	4m 56s
e2e-docker (npm)	4m 11s
setup-matrix (nuget)	3m 11s
dispatch-tests	11s
lint-ecosystems	9s
e2e-docker (nuget)	4m 11s
e2e-docker (cargo)	4m 7s
e2e-docker (composer)	4m 4s
setup-matrix (cargo)	3m 6s
setup-matrix (composer)	2m 57s
setup-matrix (golang)	2m 33s
setup-matrix (gem)	2m 57s
e2e-docker (deno)	3m 58s
setup-matrix (maven)	4m 10s
coverage-docker (maven)	5m 11s
e2e-docker (gem)	4m 15s
clippy	48s
e2e-docker (maven)	4m 33s
setup-matrix (deno)	2m 29s
coverage-docker (deno)	5m 12s
coverage-docker (cargo)	5m 0s
coverage-docker (golang)	4m 56s
setup-matrix (pypi)	4m 29s
test (macos-latest)	8m 26s
coverage	6m 13s
coverage-docker (gem)	4m 58s
e2e-docker (pypi)	4m 15s
setup-matrix (npm)	3m 34s
coverage-docker (npm)	4m 50s
coverage-docker (composer)	4m 27s
e2e-docker (golang)	4m 6s
coverage-merge	28s
e2e (ubuntu-latest, e2e_composer)	1m 30s
e2e (windows-latest, e2e_safety_cargo_build)	4m 15s
e2e (windows-latest, e2e_safety_pnpm)	4m 15s
e2e (macos-latest, e2e_safety_cargo_build)	1m 48s
e2e (ubuntu-latest, e2e_safety_cargo_build)	1m 15s
e2e (ubuntu-latest, e2e_golang)	1m 35s
e2e (ubuntu-latest, e2e_nuget)	1m 31s
e2e (macos-latest, e2e_safety_pnpm)	1m 53s
e2e (ubuntu-latest, e2e_maven)	1m 34s
e2e (ubuntu-latest, e2e_safety_pnpm)	1m 44s
e2e (ubuntu-latest, e2e_cargo)	1m 37s
	3h 29m 50s

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