fix(FN-3794): pass unload context and isolate WhatsApp sessions per project

- Extend PluginOnUnload to receive runtime context and wire ctx through plugin-loader unload hooks
- Scope WhatsApp chat plugin connections by project root to avoid cross-project session leakage
- Update plugin authoring docs and add a patch changeset for @runfusion/fusion
- Align plugin test suites across WhatsApp and example/runtime plugins with the new onUnload context contract

Fusion-Task-Id: FN-3794

packages/core/src/__tests__/plugin-loader.test.ts

@@ -129,6 +129,8 @@ function droidPluginModulePath(): string {
 // Mock TaskStore for testing
 const mockTaskStore = {
   logActivity: vi.fn(),
+  getRootDir: () => "/tmp/plugin-loader-test-root",
+  getPluginStore: vi.fn(),
 } as any;
 
 type MockStructuredLogger = {
@@ -785,6 +787,42 @@ export default plugin;
       expect(loader.isPluginLoaded("remove-test")).toBe(false);
     });
 
+    it("passes plugin context to onUnload", async () => {
+      await pluginStore.init();
+
+      const plugin = makePlugin(makeManifest({ id: "stop-context-test" }));
+      const pluginDir = join(rootDir, "plugins");
+      const pluginPath = await writePluginWithHooks(
+        pluginDir,
+        "stop-context.js",
+        {
+          onUnload:
+            "(ctx => { globalThis.__pluginUnloadCtx = { pluginId: ctx.pluginId, taskStore: ctx.taskStore }; })",
+        },
+        plugin.manifest,
+      );
+
+      await pluginStore.registerPlugin({
+        manifest: plugin.manifest,
+        path: pluginPath,
+      });
+
+      const loader = new PluginLoader({
+        pluginStore,
+        taskStore: mockTaskStore,
+      });
+
+      await loader.loadPlugin("stop-context-test");
+      await loader.stopPlugin("stop-context-test");
+
+      const unloadCtx = (globalThis as { __pluginUnloadCtx?: { pluginId: string; taskStore: unknown } })
+        .__pluginUnloadCtx;
+      expect(unloadCtx).toBeDefined();
+      expect(unloadCtx?.pluginId).toBe("stop-context-test");
+      expect(unloadCtx?.taskStore).toBe(mockTaskStore);
+      delete (globalThis as { __pluginUnloadCtx?: unknown }).__pluginUnloadCtx;
+    });
+
     it("no-ops for non-loaded plugin", async () => {
       await pluginStore.init();
 

packages/core/src/plugin-loader.ts

@@ -374,8 +374,9 @@ export class PluginLoader extends EventEmitter<{
 
     // Call onUnload with timeout
     try {
+      const ctx = await this.createContext(oldPlugin);
       await this.withTimeout(
-        this.safeCallHook(oldPlugin, "onUnload", []),
+        this.safeCallHook(oldPlugin, "onUnload", [ctx]),
         timeoutMs,
         `onUnload timeout for ${pluginId}`,
       );
@@ -645,8 +646,9 @@ export class PluginLoader extends EventEmitter<{
 
     try {
       // Call onUnload hook
+      const ctx = await this.createContext(plugin);
       await this.withTimeout(
-        this.safeCallHook(plugin, "onUnload", []),
+        this.safeCallHook(plugin, "onUnload", [ctx]),
         5000,
         `onUnload timeout for ${pluginId}`,
       );

packages/core/src/plugin-types.ts

@@ -154,7 +154,7 @@ export interface PluginLogger {
 /** Lifecycle hook: called when plugin is loaded */
 export type PluginOnLoad = (ctx: PluginContext) => Promise<void> | void;
 /** Lifecycle hook: called when plugin is unloaded */
-export type PluginOnUnload = () => Promise<void> | void;
+export type PluginOnUnload = (ctx: PluginContext) => Promise<void> | void;
 /** Lifecycle hook: called during database schema initialization */
 export type PluginOnSchemaInit = (db: Database) => Promise<void> | void;
 /** Lifecycle hook: called when a task is created */