fix(ci): paginate listFiles to handle PRs with 100+ changed files

Use github.paginate() instead of a single API call to ensure squad
detection works even for large PRs.

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

Author: oalanicolas

.github/workflows/pr-labeling.yml

@@ -27,7 +27,7 @@ jobs:
         uses: actions/github-script@v7
         with:
           script: |
-            const { data: files } = await github.rest.pulls.listFiles({
+            const files = await github.paginate(github.rest.pulls.listFiles, {
               owner: context.repo.owner,
               repo: context.repo.repo,
               pull_number: context.payload.pull_request.number,