chore: remove pull_request_target triggers from pr-review and labeler

pr-review: drop pull_request_target (auto-review on open/ready_for_review).
Manual /review via issue_comment is preserved and unaffected.

labeler: replace pull_request_target with workflow_dispatch to disable
automatic fork-PR labeling. Can be re-enabled by reverting this change.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: dvdksn

.github/workflows/labeler.yml

@@ -5,7 +5,7 @@ concurrency:
   cancel-in-progress: true
 
 on:
-  pull_request_target:
+  workflow_dispatch:
 
 jobs:
   labeler:

.github/workflows/pr-review.yml

@@ -5,8 +5,6 @@ on:
     types: [created]
   pull_request_review_comment:
     types: [created]
-  pull_request_target:
-    types: [ready_for_review, opened]
 
 permissions:
   contents: read