docs: document conventional commits style and unit-of-work commits in AGENTS.md

- Explicitly require small, focused commits (one per unit of work) so
  work is easy to revert and review
- Specify conventional commits format: <type>(<scope>): <summary> with
  feat/fix/docs/chore/refactor/test/perf/build/ci types, matching the
  alkcall repo's established pattern

AGENTS.md

@@ -12,6 +12,11 @@ verified (build + lint + tests pass), commit and push to `origin/main`
 without asking. This overrides the built-in default of "only commit when
 explicitly asked."
 
+Commit in small, focused units — one commit per unit of work (a fix, a
+feature, a doc change), not one large commit covering many topics. This
+keeps each unit of work isolated and easy to revert or review if
+something goes wrong. Push regularly so work is never stranded locally.
+
 The workflow:
 
 1. Make the change
@@ -19,9 +24,12 @@ The workflow:
    `cargo fmt --check`, `cargo doc --no-deps` if docs changed
 3. Inspect `git status` and `git diff` before staging — stage only the
    intended files, never secrets
-4. Write a concise commit message matching the repo style (see `git log
-   --oneline -10`). For multi-point changes, use a summary line plus a
-   body with bullet points and a verification block.
+4. Write a concise commit message in **conventional commits** style:
+   `<type>(<scope>): <summary>` — types are `feat`, `fix`, `docs`,
+   `chore`, `refactor`, `test`, `perf`, `build`, `ci`; the scope is
+   optional (e.g. `docs(review 002): ...`). For multi-point changes, use
+   a summary line plus a body with bullet points and a verification
+   block.
 5. `git push origin main`
 6. Report the commit hash and the verification summary