ci: add Rockchip build workflow for fork

- Builds and publishes to ghcr.io/elasticdotventures/frigate
- Triggers on push to dev and fix-rk3588s-support branches
- Can be manually triggered via workflow_dispatch
- Tags: {sha}-rk and latest-rk

.github/workflows/build-rk.yml

@@ -0,0 +1,66 @@
+name: Build Rockchip
+
+on:
+  workflow_dispatch:
+  push:
+    branches:
+      - dev
+      - fix-rk3588s-support
+
+concurrency:
+  group: ${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  rockchip_build:
+    runs-on: ubuntu-latest
+    name: Build Rockchip Image
+    permissions:
+      contents: read
+      packages: write
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v4
+      
+      - id: lowercaseRepo
+        uses: ASzc/change-string-case-action@v6
+        with:
+          string: ${{ github.repository }}
+      
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+      
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      
+      - name: Log in to GitHub Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+      
+      - name: Create version file
+        run: make version
+      
+      - name: Create short sha
+        id: sha
+        run: echo "SHORT_SHA=${GITHUB_SHA::7}" >> $GITHUB_OUTPUT
+      
+      - name: Build and push Rockchip image
+        uses: docker/bake-action@v5
+        with:
+          push: true
+          targets: rk
+          files: docker/rockchip/rk.hcl
+          set: |
+            rk.tags=ghcr.io/${{ steps.lowercaseRepo.outputs.lowercase }}:${{ steps.sha.outputs.SHORT_SHA }}-rk
+            rk.tags=ghcr.io/${{ steps.lowercaseRepo.outputs.lowercase }}:latest-rk
+            *.cache-from=type=gha
+            *.cache-to=type=gha,mode=max
+      
+      - name: Show image tags
+        run: |
+          echo "Images published:"
+          echo "  ghcr.io/${{ steps.lowercaseRepo.outputs.lowercase }}:${{ steps.sha.outputs.SHORT_SHA }}-rk"
+          echo "  ghcr.io/${{ steps.lowercaseRepo.outputs.lowercase }}:latest-rk"