ci: lint PR titles on pull_request instead of pull_request_target

pull_request_target runs with a writable token in the base-branch context;
this check only needs to read the PR title, so the safer trigger is enough.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: f0reachARR

.github/workflows/pr-title.yml

@@ -4,8 +4,10 @@ name: PR title
 # squash merges the PR title becomes that commit message, so it has to follow
 # Conventional Commits.
 on:
-    pull_request_target:
-        types: [opened, reopened, edited]
+    # `synchronize` is here so the check re-reports on every push, which matters
+    # if this is made a required check.
+    pull_request:
+        types: [opened, reopened, edited, synchronize]
 
 permissions:
     pull-requests: read