docs: document git commit conventions for all sessions

Author: creatornader

CLAUDE.md

@@ -396,3 +396,18 @@ outside the repo; CI skips it silently when no wordlist is present.
 - TypeScript strict mode.
 - No `any` types. The spec defines exact shapes; use them.
 - Error handling follows the degradation contract ([§5.8](atrib-spec.md#58-degradation-contract)): catch everything, log with `atrib:` prefix, never throw to caller.
+
+### Git commit conventions (all sessions, local or hosted)
+
+Before committing, set the repository git identity to the maintainer's:
+`git config user.name "Nader Helmy"` and
+`git config user.email creator.nader@gmail.com`. Hosted sessions ship their
+own default identity; do not commit under it.
+
+Message rules:
+
+- Conventional prefix (`feat:`, `fix:`, `docs:`, `test:`, `style:`, `chore:`, `ci:`), imperative mood, subject ≤72 characters.
+- One idea per subject; no em dashes, metrics, or promotional framing.
+- No attribution trailers of any kind (`Co-Authored-By`, session links, generated-with lines).
+- Body optional; when present, add reviewer context rather than re-describing the diff.
+- Think first, commit once: no immediate follow-up commits reworking the same change.