Add user README and refactor demo launch scripts

.env.example

@@ -1,6 +1,9 @@
 DISPLAY=:1
 HOST_DATA_PATH=./data
 
+# Default base image avoids anonymous Docker Hub pull-rate limits.
+BASE_IMAGE=public.ecr.aws/ubuntu/ubuntu:22.04
+
 # These versions mirror the upstream event-driven Dockerfile as a starting point.
 YCM_VERSION=v0.15.2
 YARP_VERSION=v3.8.0

.github/workflows/publish-image.yml

@@ -0,0 +1,58 @@
+name: Publish image to GHCR
+
+on:
+  workflow_dispatch:
+  push:
+    branches:
+      - main
+      - master
+    tags:
+      - "v*"
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}
+
+jobs:
+  build-and-push:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v5
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Log in to GHCR
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Extract image metadata
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+          tags: |
+            type=ref,event=branch
+            type=ref,event=tag
+            type=sha,prefix=sha-
+            type=raw,value=latest,enable={{is_default_branch}}
+
+      - name: Build and push image
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          file: ./Dockerfile
+          push: true
+          platforms: linux/amd64
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max

.github/workflows/test-image-build.yml

@@ -0,0 +1,44 @@
+name: Test image build
+
+on:
+  workflow_dispatch:
+  pull_request:
+
+jobs:
+  build-and-smoke-test:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v5
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Build image
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          file: ./Dockerfile
+          load: true
+          tags: primi-iit-docker:test
+          platforms: linux/amd64
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
+
+      - name: Smoke test installed tools
+        run: |
+          docker run --rm --entrypoint bash primi-iit-docker:test -lc '
+            set -euo pipefail
+            command -v yarp >/dev/null
+            command -v yarpmanager >/dev/null
+            command -v yarpview >/dev/null
+            command -v yarpscope >/dev/null
+            command -v yarpdataplayer >/dev/null
+            command -v vFramer >/dev/null
+            command -v start-yarpserver >/dev/null
+            command -v container-entrypoint >/dev/null
+            yarp check
+          '