feat: add scheduled cleanup workflow (weekly auto-cleanup)

.gitea/workflows/cleanup.yml

@@ -0,0 +1,33 @@
+name: Scheduled Cleanup
+on:
+  schedule:
+    - cron: '0 0 * * 0' # Every Sunday at 00:00
+
+jobs:
+  cleanup:
+    runs-on: macos-arm64
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      
+      - name: Clean test databases
+        run: |
+          find data/users -name "test_*.sqlite" -type f -delete || true
+          echo "Cleaned test databases"
+      
+      - name: Clean cache tmp files
+        run: |
+          find data/cache -name "*.tmp" -type f -delete || true
+          echo "Cleaned cache tmp files"
+      
+      - name: Clean log files
+        run: |
+          find . -name "*.log" -type f -delete || true
+          find . -name "*.tmp" -type f -delete || true
+          echo "Cleaned log/tmp files"
+      
+      - name: Summary
+        run: |
+          echo "::summary::Cleanup completed at $(date)"
+          remaining=$(ls data/users/*.sqlite 2>/dev/null | grep -v test_ | wc -l || echo 0)
+          echo "Remaining production databases: $remaining"