fix: handle local VPS changes during deploy by using git reset --hard instead of pull

Switches from git pull --ff-only to git fetch + git reset --hard
origin/main to avoid failing when VPS has uncommitted local changes
to tracked files (apps/ml-service/Dockerfile, docker-compose.yml).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.github/workflows/deploy.yml

@@ -118,8 +118,8 @@ jobs:
             fi
 
             cd "$DEPLOY_PATH"
-            git checkout main
-            git pull --ff-only origin main
+            git fetch origin main
+            git reset --hard origin/main
 
             {
               printf 'GITHUB_REPOSITORY=%s\n' "$REPO_SLUG"