fix: use --autostash on git pull --rebase in scholar_sync workflow

The fetch_scholar.py script writes data/*.json files before the rebase
step, causing "unstaged changes" to block git pull --rebase. --autostash
stashes them automatically, applies the rebase, then pops the stash.

https://claude.ai/code/session_01H9ZTtwKumBU77azztFJ8Ky

Author: claude

.github/workflows/scholar_sync.yml

@@ -33,7 +33,7 @@ jobs:
         run: |
           git config user.name  "github-actions[bot]"
           git config user.email "github-actions[bot]@users.noreply.github.com"
-          git pull origin main --rebase
+          git pull origin main --rebase --autostash
           git add data/scholar_data.json data/scholar_papers.json
           git diff --cached --quiet && echo "Nothing to commit" && exit 0
           git commit -m "chore: scholar sync $(date -u +'%Y-%m-%d')"