chore: block comments that describe the edit history (#52)

Add scripts/check-comment-quality.mjs from fallow-rs/fallow with its
node:test tests. The script blocks code comments that describe the edit
history or narrate the session, such as "used to be" or "before this fix".

CI runs the tests and the --all check. The Claude Code hooks in
.claude/settings.json check edits before they land. A new AGENTS.md holds
the "Write for the reader" rule. The current tree has no findings.

The script stays identical to the fallow copy, so .fallowrc.json removes
it from the fallow health checks.

Author: BartWaardenburg

.claude/settings.json

@@ -0,0 +1,27 @@
+{
+  "hooks": {
+    "PreToolUse": [
+      {
+        "matcher": "Edit|Write|MultiEdit",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "root=$(git rev-parse --show-toplevel 2>/dev/null || pwd); node \"$root/scripts/check-comment-quality.mjs\" --claude-pre-tool",
+            "statusMessage": "Checking new comments for narration and edit history..."
+          }
+        ]
+      }
+    ],
+    "Stop": [
+      {
+        "hooks": [
+          {
+            "type": "command",
+            "command": "root=$(git rev-parse --show-toplevel 2>/dev/null || pwd); node \"$root/scripts/check-comment-quality.mjs\" --working-tree --claude-hook",
+            "statusMessage": "Checking added comments for routine narration..."
+          }
+        ]
+      }
+    ]
+  }
+}

.fallowrc.json

@@ -0,0 +1,6 @@
+{
+  "$schema": "https://raw.githubusercontent.com/fallow-rs/fallow/main/schema.json",
+  "health": {
+    "ignore": ["scripts/check-comment-quality.mjs"]
+  }
+}

.github/workflows/ci.yml

@@ -25,6 +25,10 @@ jobs:
       - run: npm run typecheck
       - run: npm run lint
       - run: npm run fmt:check
+      - name: Comments describe the code as it is now
+        run: |
+          node --test scripts/check-comment-quality.test.mjs
+          node scripts/check-comment-quality.mjs --all
       - run: npm test
       - run: npm run build
       - name: Evaluation inputs match their frozen labels and questions

AGENTS.md

@@ -0,0 +1,10 @@
+# fallow-verdict agent guide
+
+## Write for the reader
+
+Write code comments, docs, commit messages, PR text, and changelog entries
+for a reader who did not see the session. Do not put the conversation, the
+prompt, discarded attempts, or the edit history into them. Describe the code
+as it is now. For a regression, state what breaks without the code, and link
+the issue. `scripts/check-comment-quality.mjs` blocks narration and history
+comments in CI and in Claude edits.