feat(FN-3506): add discovery contract and integrate remote node discovery i

Merges node discovery onboarding (FN-3506) with two steps: a pre-registration discovery contract wired into the AddNodeModal UI, and full remote discovery integration with documentation. Also adds a local embedded runtime manager to the desktop app (FN-3404) and wires permanent-agent approval contex

Fusion-Task-Id: FN-3506

packages/dashboard/app/api/legacy.ts

@@ -5548,6 +5548,18 @@ export interface NodeProjectMappingInput {
   path: string;
 }
 
+export interface RemoteNodeDiscoveredProject {
+  id: string;
+  name: string;
+  path: string;
+  status: "active" | "paused" | "errored" | "initializing";
+  isolationMode: "in-process" | "child-process";
+}
+
+export interface RemoteNodeProjectDiscoveryResult {
+  projects: RemoteNodeDiscoveredProject[];
+}
+
 /**
  * Node onboarding payload used by dashboard UI.
  *
@@ -5746,6 +5758,14 @@ export function registerNode(input: NodeCreateInput): Promise<NodeInfo> {
   });
 }
 
+/** Discover projects from a remote node before registering it. */
+export function discoverRemoteNodeProjects(input: { url: string; apiKey?: string }): Promise<RemoteNodeProjectDiscoveryResult> {
+  return api<RemoteNodeProjectDiscoveryResult>("/nodes/discover-projects", {
+    method: "POST",
+    body: JSON.stringify(input),
+  });
+}
+
 /** Fetch a single node by ID */
 export function fetchNode(id: string): Promise<NodeInfo> {
   return api<NodeInfo>(`/nodes/${encodeURIComponent(id)}`);