docs/specs and docs/plans were retired (prior commit); the source/test
comments that cited them ("spec 0050 §4.1", "spec §Testing N", "per spec",
"the spec's ...") now point at nothing. Strip every such pointer while
preserving the technical substance, the design-ledger contract refs
(C1/C11/C20/C34/C12.1/...), and the Gitea issue refs (#41).
Comment/doc edits only across 20 files — no logic change; full workspace
suite green, clippy clean.
Brummel
d858caf67b