fix: deduplicate desktop notifications and tighten notification text extraction

Desktop notifications no longer duplicate when native delivery succeeds
Reasoning chain-of-thought is excluded from notification body text
Untyped message parts are ignored in notification text extraction

packages/web/server/lib/notifications/template-runtime.test.js

@@ -30,3 +30,55 @@ describe('notification template runtime zen models', () => {
     await expect(runtime.resolveZenModel()).resolves.toBe('trinity-large-preview-free');
   });
 });
+
+describe('notification template message extraction', () => {
+  afterEach(() => {
+    globalThis.fetch = originalFetch;
+  });
+
+  it('excludes reasoning parts from payload message text', () => {
+    const runtime = createRuntime();
+
+    expect(runtime.extractLastMessageText({
+      properties: {
+        info: {
+          parts: [
+            { type: 'reasoning', text: 'private chain of thought' },
+            { type: 'text', text: 'final answer' },
+          ],
+        },
+      },
+    })).toBe('final answer');
+  });
+
+  it('ignores untyped parts even when they contain text', () => {
+    const runtime = createRuntime();
+
+    expect(runtime.extractLastMessageText({
+      properties: {
+        info: {
+          parts: [
+            { text: 'untyped text' },
+            { content: 'untyped content' },
+            { type: 'text', text: 'typed final answer' },
+          ],
+        },
+      },
+    })).toBe('typed final answer');
+  });
+
+  it('excludes reasoning parts when fetching assistant messages', async () => {
+    const runtime = createRuntime();
+    globalThis.fetch = vi.fn(async () => new Response(JSON.stringify([
+      {
+        info: { id: 'msg-1', role: 'assistant', finish: 'stop' },
+        parts: [
+          { type: 'reasoning', text: 'private chain of thought' },
+          { type: 'text', text: 'final answer' },
+        ],
+      },
+    ])));
+
+    await expect(runtime.fetchLastAssistantMessageText('session-1', 'msg-1')).resolves.toBe('final answer');
+  });
+});