Add CI workflow and update Docker/.NET configs

.gitea/workflows/build.yml

@@ -0,0 +1,53 @@
+name: Build & Deploy MinAttest
+
+on:
+  push:
+    branches: [ "main" ]
+
+jobs:
+  build:
+    runs-on: docker
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Log in to Gitea Container Registry
+        run: echo "${{ secrets.REGISTRY_TOKEN }}" | docker login gitea.theriise.net -u steinhelge --password-stdin
+
+      #
+      # Frontend
+      #
+      - name: Build Frontend
+        run: |
+          docker build -t gitea.theriise.net/steinhelge/minattest-frontend:latest frontend
+
+      - name: Push Frontend
+        run: docker push gitea.theriise.net/steinhelge/minattest-frontend:latest
+
+      #
+      # Backend API
+      #
+      - name: Build API
+        run: |
+          docker build \
+            -t gitea.theriise.net/steinhelge/minattest-api:latest \
+            -f backend/Dockerfile \
+            backend
+
+      - name: Push API
+        run: docker push gitea.theriise.net/steinhelge/minattest-api:latest
+
+      #
+      # App-host (BFF)
+      #
+      - name: Build App Host
+        run: |
+          docker build \
+            -t gitea.theriise.net/steinhelge/minattest-apphost:latest \
+            -f app-host/Dockerfile \
+            app-host
+
+      - name: Push App Host
+        run: docker push gitea.theriise.net/steinhelge/minattest-apphost:latest
+