fix(update): conventional commit message with the template version

templates.py

@@ -95,6 +95,17 @@ def git_dirty() -> bool:
     return bool(result.stdout.strip())
 
 
+def update_message(answers: Path) -> str:
+    """Conventional commit for a template update, with the version it moved to."""
+    ref = ""
+    for line in answers.read_text(encoding="utf-8").splitlines():
+        if line.startswith("_commit:"):
+            ref = line.split(":", 1)[1].strip().strip("'\"")
+            break
+    scope = answers.stem
+    return f"chore({scope}): update template to {ref}" if ref else f"chore({scope}): update template"
+
+
 def update(args: argparse.Namespace) -> None:
     answers = sorted(Path(".copier").glob("*.yml"))
     if args.parts:
@@ -108,7 +119,7 @@ def update(args: argparse.Namespace) -> None:
                    skip_answered=not args.ask, defaults=args.defaults, vcs_ref=REF)
         if git_dirty():
             subprocess.run(["git", "add", "-A"], check=True)
-            subprocess.run(["git", "commit", "-qm", f"Update {file.stem} template"], check=True)
+            subprocess.run(["git", "commit", "-qm", update_message(file)], check=True)
             print(f"committed {file.stem} update")