Add Gitea workflow for Docker image builds

.gitea/workflows/docker-build.yml

@@ -0,0 +1,37 @@
+# Build and push the TLC Search Docker image whenever changes land on master.
+name: docker-build
+
+on:
+  push:
+    branches:
+      - master
+
+env:
+  IMAGE_NAME: gitea.ghost.tel/knight/tlc-search
+
+jobs:
+  build:
+    runs-on: docker
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Log in to registry
+        uses: docker/login-action@v2
+        with:
+          registry: gitea.ghost.tel
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+
+      - name: Build and push image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: Dockerfile
+          push: true
+          tags: |
+            ${{ env.IMAGE_NAME }}:latest
+            ${{ env.IMAGE_NAME }}:${{ github.sha }}