ci(github): add develop workflow

Introduce a GitHub Actions workflow for the `main` branch that builds and pushes a Docker image to GitHub Container Registry. Includes concurrency control, permissions, Docker Buildx setup, and caching configuration.

.github/workflows/develop.yml

@@ -0,0 +1,44 @@
+name: Develop
+
+on:
+  push:
+    branches:
+      - main
+
+concurrency:
+  group: develop-${{ github.ref }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read
+  packages: write
+
+env:
+  IMAGE: ghcr.io/vvzvlad/gitmost
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Login to GitHub Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Build and push develop image
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          platforms: linux/amd64
+          push: true
+          tags: ${{ env.IMAGE }}:develop
+          cache-from: type=gha,scope=develop-amd64
+          cache-to: type=gha,scope=develop-amd64,mode=max