feat(agent): support Responses steering and project-aware tools

Use the dedicated TJWATER_AGENT_URL and Responses stream protocol. Keep running
turns active while users steer or queue follow-ups and edit pending delivery.
Refresh the model catalog before generation and preserve approval mode selection.

Integrate scoped investigation messaging/presentation, geographic place selection,
current Agent composer styles and supporting workbench contracts.

Validation: 77 focused Vitest checks, 21 browser cases, lint, typecheck and
production build. Preserve direct Server/Agent routing and project authentication.

tests/browser/support/mock-agent-api.ts

@@ -1,3 +1,4 @@
+import { responsesFixture } from "./responses-fixture";
 import type { Page } from "@playwright/test";
 
 type MockAgentApiOptions = {
@@ -19,7 +20,7 @@ export async function mockAgentApi(page: Page, options: MockAgentApiOptions = {}
     icon: "bolt" as const
   };
   const triggeredSessions = new Map<string, { sessionId: string; triggerId: string }>();
-  await page.route("**/api/v1/agent/chat/**", async (route) => {
+  await page.route("http://127.0.0.1:8787/api/v1/**", async (route) => {
     if (route.request().method() === "OPTIONS") {
       await route.fulfill({
         status: 204,
@@ -34,6 +35,18 @@ export async function mockAgentApi(page: Page, options: MockAgentApiOptions = {}
 
     const pathname = new URL(route.request().url()).pathname;
 
+    if (pathname.endsWith("/suggestions") && route.request().method() === "POST") {
+      await route.fulfill({ headers: corsHeaders, json: {
+        suggestions: [
+          { question: "分析当前管网需要优先核对的压力监测点。", activity_id: null },
+          { question: "检查近期供水任务的证据与待确认事项。", activity_id: null },
+          { question: "解读近期分析成果并列出进一步验证的问题。", activity_id: null },
+        ],
+        generated_at: "2026-10-09T07:00:00Z",
+      } });
+      return;
+    }
+
     const collaborationMatch = pathname.match(/\/task\/([^/]+)\/collaboration\/session$/);
     if (collaborationMatch && route.request().method() === "POST") {
       await route.fulfill({
@@ -99,24 +112,21 @@ export async function mockAgentApi(page: Page, options: MockAgentApiOptions = {}
       return;
     }
 
-    if (pathname.endsWith("/stream")) {
+    if (pathname.endsWith("/responses")) {
       await route.fulfill({
         status: 200,
         headers: {
           ...corsHeaders,
           "Cache-Control": "no-cache",
-          "Content-Type": "text/event-stream",
-          "X-Vercel-AI-UI-Message-Stream": "v1"
+          "Content-Type": "text/event-stream"
         },
-        body: [
+        body: responsesFixture([
           { type: "start", messageId: "assistant-browser-test" },
           { type: "text-start", id: "answer" },
           { type: "text-delta", id: "answer", delta: "已收到工况汇总请求。" },
           { type: "text-end", id: "answer" },
           { type: "finish", finishReason: "stop" }
-        ]
-          .map((part) => `data: ${JSON.stringify(part)}\n\n`)
-          .join("")
+        ])
       });
       return;
     }
@@ -161,6 +171,6 @@ export async function mockAgentApi(page: Page, options: MockAgentApiOptions = {}
       return;
     }
 
-    await route.fulfill({ headers: corsHeaders, json: {} });
+    await route.fallback();
   });
 }