chore: add Renovate configuration and workflows

- Introduced .renovaterc for Renovate settings.
- Added renovate.config.cjs for Gitea integration.
- Created .gitea/workflows/renovate.yml for daily Renovate runs.
- Added .gitea/workflows/test.yml for CI testing.
- Removed outdated GitHub workflows and configuration files.

.gitea/workflows/renovate.yml

@@ -0,0 +1,27 @@
+name: RenovateBot
+
+on:
+  schedule:
+    - cron: "@daily"
+  push:
+    branches:
+      - master
+
+jobs:
+  renovate:
+    container: ghcr.io/renovatebot/renovate:43
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v6
+
+      - name: Run renovate
+        run: |
+          renovate
+        env:
+          LOG_LEVEL: ${{ vars.RENOVATE_LOG_LEVEL }}
+          RENOVATE_LOG_LEVEL: ${{ vars.RENOVATE_LOG_LEVEL }}
+          RENOVATE_CONFIG_FILE: renovate.config.cjs
+          RENOVATE_REPOSITORIES: ${{ gitea.repository }}
+          RENOVATE_TOKEN: ${{ secrets.RENOVATE_TOKEN }}