ci(ghcr): mirror ghcr-feat-copilot workflow on main for dispatch resolution

auto-sync-upstream-copilot.yml dispatches ghcr-feat-copilot.yml after
a successful clean-merge + build:

  gh workflow run ghcr-feat-copilot.yml --repo "${{ github.repository }}" \
                --ref "${TARGET_BRANCH}"

GitHub Actions requires workflows triggered via workflow_dispatch to
exist on the default branch. The file only lived on feat/copilot, so
the dispatch step would fail with 'workflow not found'.

The push event from auto-sync (which uses GITHUB_TOKEN) does not
cascade to ghcr-feat-copilot's 'on: push' trigger — that's a
documented GitHub Actions safety to prevent recursion. The explicit
dispatch is the supported workaround.

This mirrors the precedent set in 8a2e2e0, which added
ghcr-remote-fix.yml to main for the same reason.

The main copy is byte-identical to the feat/copilot copy. Since the
'on: push: branches: [feat/copilot]' filter excludes main, the file
on main is purely a dispatch resolution stub — actual builds still
run against the feat/copilot ref.

Author: conversun

.github/workflows/ghcr-feat-copilot.yml

@@ -0,0 +1,60 @@
+name: ghcr-feat-copilot
+
+on:
+  workflow_dispatch:
+  push:
+    branches:
+      - feat/copilot
+
+env:
+  IMAGE: ghcr.io/${{ github.repository_owner }}/cli-proxy-api
+
+jobs:
+  build-and-push:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Refresh models catalog
+        run: |
+          git fetch --depth 1 https://github.com/router-for-me/models.git main
+          git show FETCH_HEAD:models.json > internal/registry/models/models.json
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Login to GHCR
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Lowercase image name
+        run: echo "IMAGE=$(echo '${{ env.IMAGE }}' | tr '[:upper:]' '[:lower:]')" >> $GITHUB_ENV
+
+      - name: Generate Build Metadata
+        run: |
+          echo "VERSION=feat-copilot" >> $GITHUB_ENV
+          echo "COMMIT=$(git rev-parse --short HEAD)" >> $GITHUB_ENV
+          echo "BUILD_DATE=$(date -u +%Y-%m-%dT%H:%M:%SZ)" >> $GITHUB_ENV
+
+      - name: Build and push (amd64)
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          platforms: linux/amd64
+          push: true
+          build-args: |
+            VERSION=${{ env.VERSION }}
+            COMMIT=${{ env.COMMIT }}
+            BUILD_DATE=${{ env.BUILD_DATE }}
+          tags: |
+            ${{ env.IMAGE }}:feat-copilot
+            ${{ env.IMAGE }}:feat-copilot-${{ env.COMMIT }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max