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/plugins/PluginDashboardViewHost.tsx

@@ -0,0 +1,20 @@
+import { resolvePluginDashboardView, MissingPluginDashboardView, parsePluginTaskViewId } from "./pluginViewRegistry";
+import type { PluginDashboardHostContext, PluginTaskView } from "./pluginViewRegistry";
+
+export function PluginDashboardViewHost({
+  taskView,
+  context,
+}: {
+  taskView: PluginTaskView;
+  context: PluginDashboardHostContext;
+}) {
+  const parsed = parsePluginTaskViewId(taskView);
+  if (!parsed) return null;
+
+  const ViewComponent = resolvePluginDashboardView(parsed.pluginId, parsed.viewId);
+  if (!ViewComponent) {
+    return <>{MissingPluginDashboardView({ pluginId: parsed.pluginId, viewId: parsed.viewId })}</>;
+  }
+
+  return <ViewComponent context={context} />;
+}

packages/dashboard/app/plugins/pluginViewRegistry.css

@@ -0,0 +1,27 @@
+.plugin-dashboard-view-missing {
+  margin: var(--space-lg);
+  padding: var(--space-lg);
+  display: flex;
+  flex-direction: column;
+  gap: var(--space-md);
+}
+
+.plugin-dashboard-view-missing-title {
+  margin: 0;
+  display: flex;
+  align-items: center;
+  gap: var(--space-sm);
+  font-size: 1rem;
+}
+
+.plugin-dashboard-view-missing-description {
+  margin: 0;
+  color: var(--text-muted);
+}
+
+@media (max-width: 768px) {
+  .plugin-dashboard-view-missing {
+    margin: var(--space-md);
+    padding: var(--space-md);
+  }
+}

packages/dashboard/app/plugins/pluginViewRegistry.tsx

@@ -0,0 +1,64 @@
+import { AlertTriangle } from "lucide-react";
+import type { ComponentType, ReactNode } from "react";
+import type { Task, TaskDetail, WorkflowStep } from "@fusion/core";
+import { DependencyGraphView } from "@fusion-plugin-examples/dependency-graph/dashboard-view";
+import "./pluginViewRegistry.css";
+
+export type PluginTaskView = `plugin:${string}:${string}`;
+
+export interface PluginDashboardHostContext {
+  projectId?: string;
+  tasks: Task[];
+  workflowSteps: WorkflowStep[];
+  openTaskDetail: (task: Task | TaskDetail, initialTab?: "logs" | "changes") => void;
+  renderTaskCard: (task: Task) => ReactNode;
+}
+
+export interface PluginDashboardViewComponentProps {
+  context: PluginDashboardHostContext;
+}
+
+export interface PluginDashboardViewRegistration {
+  pluginId: string;
+  viewId: string;
+  component: ComponentType<PluginDashboardViewComponentProps>;
+}
+
+const REGISTRY: PluginDashboardViewRegistration[] = [
+  {
+    pluginId: "fusion-plugin-dependency-graph",
+    viewId: "graph",
+    component: DependencyGraphView as ComponentType<PluginDashboardViewComponentProps>,
+  },
+];
+
+export function buildPluginTaskViewId(pluginId: string, viewId: string): PluginTaskView {
+  return `plugin:${pluginId}:${viewId}`;
+}
+
+export function parsePluginTaskViewId(taskView: string): { pluginId: string; viewId: string } | null {
+  if (!taskView.startsWith("plugin:")) return null;
+  const [, pluginId, ...viewParts] = taskView.split(":");
+  const viewId = viewParts.join(":");
+  if (!pluginId || !viewId) return null;
+  return { pluginId, viewId };
+}
+
+export function resolvePluginDashboardView(pluginId: string, viewId: string): ComponentType<PluginDashboardViewComponentProps> | null {
+  const hit = REGISTRY.find((entry) => entry.pluginId === pluginId && entry.viewId === viewId);
+  return hit?.component ?? null;
+}
+
+export function MissingPluginDashboardView({ pluginId, viewId }: { pluginId: string; viewId: string }): ReactNode {
+  return (
+    <section className="card plugin-dashboard-view-missing">
+      <h2 className="plugin-dashboard-view-missing-title">
+        <AlertTriangle />
+        Plugin view unavailable
+      </h2>
+      <p className="plugin-dashboard-view-missing-description">
+        The dashboard could not resolve <code>{pluginId}:{viewId}</code> from the host registry.
+      </p>
+    </section>
+  );
+}