feat(FN-3079): add plugin dashboard views and dependency graph plugin

- Add plugin dashboard view registration and hosting across core, dashboard routes, and plugin SDK exports
- Integrate plugin-provided views into app navigation, mobile/header UI, and view state hooks with coverage
- Add fusion-plugin-dependency-graph example plugin with persisted storage, dashboard view UI, and manifest wiring
- Update plugin authoring and architecture docs for dashboard view extension points
- Add a changeset for @runfusion/fusion covering plugin dashboard view support

Fusion-Task-Id: FN-3079

packages/dashboard/app/hooks/__tests__/usePluginDashboardViews.test.ts

@@ -0,0 +1,42 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { renderHook, waitFor } from "@testing-library/react";
+import { usePluginDashboardViews, __test_clearDashboardViewsCache } from "../usePluginDashboardViews";
+import * as api from "../../api";
+
+vi.mock("../../api", () => ({
+  fetchPluginDashboardViews: vi.fn(),
+}));
+
+const mockFetch = vi.mocked(api.fetchPluginDashboardViews);
+
+describe("usePluginDashboardViews", () => {
+  beforeEach(() => {
+    __test_clearDashboardViewsCache();
+    mockFetch.mockReset();
+  });
+
+  it("fetches and returns dashboard views", async () => {
+    mockFetch.mockResolvedValueOnce([
+      { pluginId: "dep", view: { viewId: "graph", label: "Graph", componentPath: "./Graph.js" } },
+    ]);
+
+    const { result } = renderHook(() => usePluginDashboardViews());
+    await waitFor(() => expect(result.current.loading).toBe(false));
+    expect(result.current.views).toHaveLength(1);
+  });
+
+  it("uses project-scoped cache keys", async () => {
+    mockFetch.mockResolvedValueOnce([{ pluginId: "a", view: { viewId: "x", label: "X", componentPath: "./x.js" } }]);
+    const first = renderHook(() => usePluginDashboardViews("project-a"));
+    await waitFor(() => expect(first.result.current.loading).toBe(false));
+
+    mockFetch.mockClear();
+    renderHook(() => usePluginDashboardViews("project-a"));
+    expect(mockFetch).not.toHaveBeenCalled();
+
+    mockFetch.mockResolvedValueOnce([{ pluginId: "b", view: { viewId: "y", label: "Y", componentPath: "./y.js" } }]);
+    const second = renderHook(() => usePluginDashboardViews("project-b"));
+    await waitFor(() => expect(second.result.current.loading).toBe(false));
+    expect(mockFetch).toHaveBeenCalledWith("project-b");
+  });
+});

packages/dashboard/app/hooks/__tests__/useViewState.test.ts

@@ -275,6 +275,28 @@ describe("useViewState", () => {
     });
   });
 
+  it("restores and persists plugin task views using the canonical composite key", async () => {
+    localStorage.setItem("kb:proj_123:kb-dashboard-task-view", "plugin:fusion-plugin-dependency-graph:graph");
+
+    const { result } = renderHook(() =>
+      useViewState(
+        createOptions({
+          currentProject: PROJECT,
+        }),
+      ),
+    );
+
+    await waitFor(() => {
+      expect(result.current.taskView).toBe("plugin:fusion-plugin-dependency-graph:graph");
+    });
+
+    await act(async () => {
+      result.current.setTaskView("plugin:fusion-plugin-dependency-graph:graph");
+    });
+
+    expect(localStorage.getItem("kb:proj_123:kb-dashboard-task-view")).toBe("plugin:fusion-plugin-dependency-graph:graph");
+  });
+
   it("restores legacy views (board/list/agents/missions/chat) from scoped storage", async () => {
     const legacyViews = ["board", "list", "agents", "missions", "chat"] as const;