Add docker image build and deploy workflow

.github/workflows/cd.yml

@@ -0,0 +1,51 @@
+name: CD
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Cache dependencies
+        uses: actions/cache@v3
+        with:
+          path: |
+            ~/.cargo
+            target/
+          key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
+          restore-keys: ${{ runner.os }}-cargo-
+
+      - name: Install Rust
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: stable
+          override: true
+          components: rustfmt, clippy
+
+      - name: Run cargo check
+        uses: actions-rs/cargo@v1
+        with:
+          command: check
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Login to DockerHub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+
+      - name: Build and push
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          push: true

.github/workflows/ci.yml

@@ -1,5 +1,5 @@
 name: CI
-on: [push]
+on: [pull_request]
 jobs:
   audit:
     runs-on: ubuntu-latest