feat(FN-3590): prioritize workspace source entry for bundled plugins and ad

This merge introduces eval score categorization with a new `eval-scoring.ts` module (FN-3601, FN-3390), hardened bundled plugin entry resolution to prioritize workspace source over installed copies (FN-3590), and documented reply-link threading behavior in the mailbox (FN-3598). It also adds mobile

Fusion-Task-Id: FN-3590

packages/dashboard/src/__tests__/plugin-routes.routes.test.ts

@@ -328,7 +328,7 @@ describe("GET /plugins/:id/settings", () => {
     expect(res.body).toEqual({ apiKey: "secret", enabled: true });
   });
 
-  it("returns 404 for non-existent plugin", async () => {
+  it("returns 404 for non-existent non-bundled plugin", async () => {
     (pluginStore.getPlugin as ReturnType<typeof vi.fn>).mockRejectedValueOnce(
       Object.assign(new Error('Plugin "nonexistent" not found'), { code: "ENOENT" }),
     );
@@ -339,6 +339,17 @@ describe("GET /plugins/:id/settings", () => {
     expect(res.body).toHaveProperty("error");
   });
 
+  it("returns empty settings for bundled runtime plugin before first install", async () => {
+    (pluginStore.getPlugin as ReturnType<typeof vi.fn>).mockRejectedValueOnce(
+      Object.assign(new Error('Plugin "fusion-plugin-hermes-runtime" not found'), { code: "ENOENT" }),
+    );
+
+    const res = await GET(buildApp(), "/api/plugins/fusion-plugin-hermes-runtime/settings");
+
+    expect(res.status).toBe(200);
+    expect(res.body).toEqual({});
+  });
+
   it("supports projectId query param scoping", async () => {
     const scopedPluginStore = createMockPluginStore();
     (scopedPluginStore.getPlugin as ReturnType<typeof vi.fn>).mockResolvedValueOnce({
@@ -1054,6 +1065,23 @@ describe("PUT /plugins/:id/settings auto-install for bundled runtime plugins", (
     expect(ensure).not.toHaveBeenCalled();
   });
 
+  it("returns 500 with intentional message when bundled auto-install reports missing bundle", async () => {
+    (pluginStore.getPlugin as ReturnType<typeof vi.fn>).mockRejectedValueOnce(
+      new Error("Plugin not found"),
+    );
+    const ensure = vi.fn().mockResolvedValue(false);
+
+    const res = await REQUEST(
+      buildAppWithBundleHook(ensure),
+      "PUT",
+      "/api/plugins/fusion-plugin-hermes-runtime/settings",
+      { settings: { apiKey: "k" } },
+    );
+
+    expect(res.status).toBe(500);
+    expect(res.body.error).toContain("is unavailable in this build");
+  });
+
   it("returns 500 when auto-install throws", async () => {
     (pluginStore.getPlugin as ReturnType<typeof vi.fn>).mockRejectedValueOnce(
       new Error("Plugin not found"),

packages/dashboard/src/routes.ts

@@ -3247,7 +3247,15 @@ export function createApiRoutes(store: TaskStore, options?: ServerOptions): Rout
       const plugin = await pluginStore.getPlugin(id);
       res.json(plugin.settings);
     } catch (err: unknown) {
-      if (err instanceof Error && (err instanceof Error ? err.message : String(err)).includes("not found")) {
+      const isNotFoundError = err instanceof Error && (err instanceof Error ? err.message : String(err)).includes("not found");
+      const isBundledFallback = BUNDLED_PLUGIN_RUNTIMES.some((r) => r.pluginId === id);
+      if (isNotFoundError && isBundledFallback) {
+        // Bundled runtime plugins can be surfaced in settings before they've
+        // been lazily installed. Return empty defaults so cards can open.
+        res.json({});
+        return;
+      }
+      if (isNotFoundError) {
         throw notFound(`Plugin "${id}" not found`);
       }
       throw internalError(err instanceof Error ? err.message : "Unknown error");
@@ -3606,8 +3614,16 @@ export function createApiRoutes(store: TaskStore, options?: ServerOptions): Rout
       }
       if (!alreadyRegistered) {
         try {
-          await options.ensureBundledPluginInstalled(id);
+          const installOk = await options.ensureBundledPluginInstalled(id);
+          if (!installOk) {
+            throw internalError(
+              `Bundled plugin "${id}" is unavailable in this build and could not be auto-installed`,
+            );
+          }
         } catch (installErr) {
+          if (installErr instanceof ApiError) {
+            throw installErr;
+          }
           throw internalError(
             `Failed to auto-install bundled plugin "${id}": ${installErr instanceof Error ? installErr.message : String(installErr)}`,
           );