Add GitHub Actions: build & push Docker image to Docker Hub

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.github/workflows/docker-publish.yml

@@ -0,0 +1,47 @@
+name: Build & Push Docker image
+
+# Builds the stack image (headless Chrome + gpt/gemini extensions + monitor gateway)
+# on GitHub's runners and pushes it to Docker Hub. No local Docker needed.
+on:
+  push:
+    branches: [main]
+    paths:
+      - "Dockerfile"
+      - "start_hf.sh"
+      - "monitor/**"
+      - "profilesync/**"
+      - "free-Chatgpt-api/**"
+      - "free-gemini-api/**"
+      - ".github/workflows/docker-publish.yml"
+  workflow_dispatch: {}   # allow manual "Run workflow" from the Actions tab
+
+env:
+  IMAGE: akashyadav758/free-self-api-server
+
+jobs:
+  build-and-push:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Log in to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+      - name: Build and push
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          file: ./Dockerfile
+          push: true
+          tags: |
+            ${{ env.IMAGE }}:latest
+            ${{ env.IMAGE }}:${{ github.sha }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max