feat: show plugin download counts only and stop CI builds inflating them

.github/workflows/pr-check.yml

@@ -24,6 +24,15 @@ jobs:
       - name: Install dependencies
         run: npm ci
 
+      # Bundled plugins are counted as downloads in the plugin store, so a
+      # build only fetches them when the pins change.
+      - name: Cache bundled plugins
+        uses: actions/cache@v6
+        with:
+          path: node_modules/.cache/termix-bundled-plugins
+          key: bundled-plugins-${{ hashFiles('docker/bundled-plugins.json') }}
+          enableCrossOsArchive: true
+
       - name: Build plugin SDK
         run: npm run build:sdk