added docker gh action

.github/workflows/docker.yml

@@ -0,0 +1,28 @@
+name: Docker
+
+on:
+  push:
+    branches: [ "main" ]
+    # paths:
+    #   - 'Cargo.toml'
+  pull_request:
+    branches: [ "main" ]
+
+env:
+  CARGO_TERM_COLOR: always
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+    - uses: cachix/install-nix-action@v31
+      with:
+        nix_path: nixpkgs=channel:nixos-unstable
+
+    - run: nix build .#docker
+    - run: docker load -i result
+    - run: docker tag docki:latest docki:$(nu -c "cargo metadata --format-version=1 --no-deps | from json | get packages | first | get version")
+    - run: docker image ls