feat!: port mutexbot actions to rust and add isolation channels (#7)

## Problem

To send notifcations for dev and prod deployments into different channels we needed to use the isolation channel feature of mutexbot.

## Summary of changes

 - Port to rust, to make dynamic inclusion of channel isolation parameters easier. It would've been possible to do this in bash, but I'm confident that the static checks done by rust will help making this less error prone in the long run.
 - Support isolation_channel parameters for reserving/releasing
 - Merge `mutexbot/reserve` and `mutexbot/release` into one `mutexbot` action to dedupe code
 - Parameters change from `kebap-case` to `snake_case`, because of rust best practices. I was not able to make rust happy with `kebap-case` in parameters. If should be possible to do that by patching https://github.com/42ByteLabs/ghactions

.github/workflows/mutexbot.yml

@@ -0,0 +1,107 @@
+name: MutexBot Container Image
+
+on:
+  pull_request:
+    branches:
+      - main
+    paths:
+      - "mutexbot/**"
+  push:
+    branches:
+      - main
+    paths:
+      - "mutexbot/**"
+    tags:
+      - "mutexbot-v*.*.*"
+
+permissions:
+  contents: read
+
+env:
+  DOCKERHUB_REPO: neondatabase/dev-actions
+
+jobs:
+  build:
+    runs-on: ${{ fromJson(format('["self-hosted", "{0}"]', matrix.platform == 'linux/arm64' && 'small-arm64' || 'small')) }}
+    outputs:
+      digest_arm64: ${{ steps.export_digest.outputs.digest_arm64 }}
+      digest_amd64: ${{ steps.export_digest.outputs.digest_amd64 }}
+    strategy:
+      fail-fast: false
+      matrix:
+        platform:
+          - linux/amd64
+          - linux/arm64
+    steps:
+      - name: Fetch mutexbot folder
+        uses: actions/checkout@v4
+        with:
+          sparse-checkout: mutexbot
+
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ${{ env.DOCKERHUB_REPO }}
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Login to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.NEON_DOCKERHUB_USERNAME }}
+          password: ${{ secrets.NEON_DOCKERHUB_PASSWORD }}
+
+      - name: Build and push by digest
+        id: build
+        uses: docker/build-push-action@v6
+        with:
+          context: mutexbot
+          platforms: ${{ matrix.platform }}
+          labels: ${{ steps.meta.outputs.labels }}
+          outputs: type=image,name=${{ env.DOCKERHUB_REPO }},push-by-digest=true,name-canonical=true,push=true
+
+      - name: Export digest
+        id: export_digest
+        run: |
+          arch="$(echo -n ${{ matrix.platform }} | sed -e 's/linux\///')"
+          digest="${{ steps.build.outputs.digest }}"
+          echo "digest_${arch}=${digest#sha256:}" >> "$GITHUB_OUTPUT"
+
+  merge:
+    runs-on: ["self-hosted", "small"]
+    needs:
+      - build
+    steps:
+      - name: Login to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.NEON_DOCKERHUB_USERNAME }}
+          password: ${{ secrets.NEON_DOCKERHUB_PASSWORD }}
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ${{ env.DOCKERHUB_REPO }}
+          tags: |
+            # branch event
+            type=ref,enable=true,priority=600,prefix=mutexbot-,suffix=,event=branch
+            # pull request event
+            type=ref,enable=true,priority=600,prefix=mutexbot-pr-,suffix=,event=pr
+            # tags event
+            type=match,pattern=mutexbot-v(.*)
+
+      - name: Create manifest list and push
+        run: |
+          docker buildx imagetools create \
+            $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \
+            ${{ env.DOCKERHUB_REPO }}@sha256:${{ needs.build.outputs.digest_arm64 }} \
+            ${{ env.DOCKERHUB_REPO }}@sha256:${{ needs.build.outputs.digest_amd64 }}
+
+      - name: Inspect image
+        run: docker buildx imagetools inspect ${{ env.DOCKERHUB_REPO }}:${{ steps.meta.outputs.version }}

mutexbot/.gitignore

@@ -0,0 +1 @@
+/target