Add our tooling to Dockerfile, restore build workflow

- Expand base apt: jq, procps, python3, python3-pip, gh
- Install kubectl, uv/uvx, kubeseal binaries
- Add @google/gemini-cli to production agent installs
- Use pnpm-lock.yaml* wildcard + --no-frozen-lockfile (lockfile policy)
- Restore build.yml targeting runners-cpfarhood

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.github/workflows/build.yml

@@ -0,0 +1,53 @@
+name: Build & Push
+
+on:
+  push:
+    branches: [master]
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  packages: write
+
+jobs:
+  build:
+    runs-on: runners-cpfarhood
+    timeout-minutes: 30
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Login to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+      - 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: Docker meta
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ghcr.io/cpfarhood/paperclip
+          tags: |
+            type=raw,value=latest
+            type=sha,prefix=
+            type=semver,pattern={{version}}
+
+      - name: Build and push
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          no-cache: true