fix(md): tolerate trailing comma in markdown island imports

packages/md/src/extract-script.ts

@@ -1,8 +1,8 @@
 const SCRIPT_RE = /^<script\b[^>]*>([\s\S]*?)<\/script>\s*\n?/;
 const ISLAND_IMPORT_RE =
-  /import\s+(\w+)\s+from\s+("[^"]+"|'[^']+')\s+with\s*\{\s*island\s*:\s*("[^"]+"|'[^']+')\s*\}/g;
+  /import\s+([$_A-Za-z][$_\w]*)\s+from\s+("[^"]+"|'[^']+')\s+with\s*\{\s*island\s*:\s*("[^"]+"|'[^']+')\s*,?\s*\}/g;
 const ISLAND_IMPORT_LINE_RE =
-  /^[ \t]*import\s+\w+\s+from\s+(?:"[^"]+"|'[^']+')\s+with\s*\{\s*island\s*:\s*(?:"[^"]+"|'[^']+')\s*\}\s*;?\s*$/gm;
+  /^[ \t]*import\s+[$_A-Za-z][$_\w]*\s+from\s+(?:"[^"]+"|'[^']+')\s+with\s*\{\s*island\s*:\s*(?:"[^"]+"|'[^']+')\s*,?\s*\}\s*;?\s*$/gm;
 
 export type IslandImport = {
   name: string;

packages/md/test/unit/extract-script.test.ts

@@ -133,4 +133,33 @@ const count = ref(0)
     const result = extractScript(source);
     expect(result.clientCode).toBe(`import { ref } from "vue"\n\nconst count = ref(0)`);
   });
+
+  it('extracts island imports with a trailing comma in the attributes', () => {
+    const source = `<script>
+import Counter from "./Counter.vue" with { island: "load", }
+</script>
+
+# Hello`;
+    const result = extractScript(source);
+    expect(result.islandImports).toHaveLength(1);
+    expect(result.islandImports[0]).toEqual({
+      name: 'Counter',
+      specifier: './Counter.vue',
+      strategy: 'load',
+    });
+    // the island import line is stripped from client code (not leaked as an orphan import)
+    expect(result.clientCode).toBeNull();
+  });
+
+  it('extracts island imports whose component name starts with $ or _', () => {
+    const source = `<script>
+import $Counter from "./Counter.vue" with { island: "load" }
+</script>
+
+# Hello`;
+    const result = extractScript(source);
+    expect(result.islandImports).toHaveLength(1);
+    expect(result.islandImports[0].name).toBe('$Counter');
+    expect(result.clientCode).toBeNull();
+  });
 });