Run the gate, the editor suite and the three games on the Gitea runner

The job image (tools/ci/Dockerfile, label game-maker-ci) carries chromium with the Vulkan
drivers, php-cli and the host's fonts; the render device itself comes from the runner's
container.options, so a job container gets the Intel GPU instead of llvmpipe.

tools/ci/serve.sh puts the checkout behind /game-maker/ with php -S and writes the project
shells the seeders need; every tool now takes its server from GAME_MAKER_BASE_URL rather than
from a project id repeated in shell scripts.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

.gitea/workflows/ci.yml

@@ -0,0 +1,38 @@
+# Runs the whole proof on the Gitea runner: gate, the editor suite and the three example games.
+#
+# `runs-on: game-maker-ci` picks the image built from tools/ci/Dockerfile. The render device and
+# /dev/shm come from the runner's own container.options (/_stacks/git/runner/config.yaml), not
+# from here – without them chromium falls back to software WebGL.
+name: game-maker
+
+on:
+  push:
+  workflow_dispatch:
+
+jobs:
+  suite:
+    runs-on: game-maker-ci
+    timeout-minutes: 45
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Versions
+        run: |
+          node --version
+          chromium --version
+          php --version | head -1
+
+      - name: Install
+        run: npm ci --no-audit --no-fund
+
+      - name: Gate
+        run: ./check.sh
+
+      - name: Build
+        run: npm run build
+
+      - name: Editor suite
+        run: tools/ci/run-e2e.sh
+
+      - name: Example games
+        run: tools/ci/run-smokes.sh