Add Gitea Actions deploy workflow

Builds Hugo and writes the output to /srv/www/www on push to master.
Runs in a node:20-bookworm container with /srv/www bind-mounted from
the shinobi host. Caddy on the host serves /srv/www/www directly.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

.gitea/workflows/deploy.yml

@@ -0,0 +1,29 @@
+name: Deploy
+
+on:
+  push:
+    branches: [master]
+  workflow_dispatch:
+
+env:
+  HUGO_VERSION: "0.151.0"
+
+jobs:
+  deploy:
+    runs-on: ubuntu-latest
+    container:
+      image: node:20-bookworm
+      volumes:
+        - /srv/www:/srv/www
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: recursive
+
+      - name: Install Hugo extended
+        run: |
+          curl -sL "https://github.com/gohugoio/hugo/releases/download/v${HUGO_VERSION}/hugo_extended_${HUGO_VERSION}_linux-arm64.tar.gz" | tar xz
+          install hugo /usr/local/bin/
+
+      - name: Build and deploy to /srv/www/www
+        run: hugo --gc --minify --cleanDestinationDir --destination /srv/www/www