Repository navigation

docs: add Signed commits section to CONTRIBUTING #375

Job	Run time
governance / Check Workflow Staleness	10s
governance / Well-Known (RFC 9116 + RSR)	6s
governance / Code quality + docs	12s
governance / Language / package anti-pattern policy	33s
governance / Guix primary / Nix fallback policy	18s
governance / Licence consistency	10s
governance / Trusted-base reduction policy	11s
governance / Security policy checks	11s
governance / Workflow security linter	8s
governance / Validate Hypatia Baseline	3m 44s
	5m 43s