docs: require roadmap updates alongside features

Two releases shipped milestones without the roadmap following, leaving it claiming that implemented capabilities were missing. Make the update part of the pull request that changes what the project claims about itself, and say plainly that correcting a stale entry matters more than appending a new one.

Author: cardmagic

AGENTS.md

@@ -28,6 +28,16 @@ Write Minitest files as `test/**/*_test.rb`. Start behavioral changes with a foc
 
 Use concise imperative subjects, preferably under 50 characters; use prefixes such as `fix:`, `ci:`, or `chore:`. Pull requests should explain API, correctness, security, migration, and compatibility effects; list exact validation commands; link issues; and include screenshots for UI or reactive ERB changes. Never bypass hooks or add AI attribution.
 
+Update `docs/roadmap.md` in the same pull request whenever the change alters
+what the project claims about itself. That includes completing or advancing a
+numbered milestone, moving an entry between "Implemented and tested" and
+"Partially implemented", and discovering a limitation worth recording, such as a
+capability that turns out to be opt-in, adapter-specific, or measured rather
+than assumed. Prefer correcting a stale entry over only appending a new one: an
+inaccurate claim misleads more than a missing one. State what was measured and
+what was not, so a reader can tell evidence from intent. A change that only
+fixes a defect, adjusts tooling, or edits prose does not need a roadmap edit.
+
 ## Release Workflow
 
 Update the version, `CHANGELOG.md`, and `Gemfile.lock`; run `bundle exec rake`; then commit and push `main`. Publish by pushing an annotated version tag: