refactor: simplify plugin dependency handling

Simplify plugin installation and runtime loading around package-manager-owned dependencies, with Jiti reserved for local/TS fallback paths.

Also scans npm plugin install roots so hoisted transitive dependencies are covered by dependency denylist and node_modules symlink checks.

extensions/matrix/src/manifest.test.ts

@@ -3,20 +3,14 @@ import { describe, expect, it } from "vitest";
 
 type MatrixPackageManifest = {
   dependencies?: Record<string, string>;
-  openclaw?: {
-    bundle?: {
-      stageRuntimeDependencies?: boolean;
-    };
-  };
 };
 
 describe("matrix package manifest", () => {
-  it("opts into staging bundled runtime dependencies", () => {
+  it("keeps runtime dependencies in the package manifest", () => {
     const packageJson = JSON.parse(
       fs.readFileSync(new URL("../package.json", import.meta.url), "utf8"),
     ) as MatrixPackageManifest;
 
     expect(packageJson.dependencies?.["fake-indexeddb"]).toBeDefined();
-    expect(packageJson.openclaw?.bundle?.stageRuntimeDependencies).toBe(true);
   });
 });