feat: direct-execute legacy create-assistant entry

CHANGELOG.md

@@ -483,5 +483,6 @@
 - 全局 `生成文案` 旧入口也已经做成相同分流：优先围绕最近完成任务直接生成，只有没有可承接任务时才回退到旧文案表单。
 # 2026-04-05
 
+- agent: 遗留 `创建 Agent` 入口现在也会优先 direct-execute，当前项目已就绪时直接创建 Agent，只有缺上下文时才回退到旧表单。
 - pipeline: 全局旧入口 `AI 视频 / 实拍剪辑` 现在也会优先围绕最近完成任务 direct-execute，只有没有可承接任务时才回退到旧表单。
 - review: `任务详情 -> 写复盘` 旧入口改成 direct-execute，带 `source_job_id` 直接生成复盘草稿，不再优先打开旧复盘表单。

web/storyforge-web-v4/assets/app.js

@@ -12070,6 +12070,14 @@ document.addEventListener("click", async (event) => {
       return;
     }
     if (name === "open-create-assistant") {
+      const project = getSelectedProject();
+      if (project?.id) {
+        await runDirectWorkbenchAction("create-assistant", {
+          busyLabel: "正在创建 Agent...",
+          errorTitle: "创建 Agent 失败"
+        });
+        return;
+      }
       openCreateAssistantAction();
       return;
     }

web/storyforge-web-v4/tests/workbench-pages.test.mjs

@@ -1045,6 +1045,9 @@ test("playbook and review high-frequency actions now reuse direct execute handle
   assert.match(clickActions, /name === "open-real-cut"[\s\S]*const fallbackJob = getLatestCompletedProjectJob\(\)/);
   assert.match(clickActions, /name === "open-real-cut"[\s\S]*runDirectWorkbenchAction\("create-real-cut"/);
   assert.match(clickActions, /name === "open-real-cut"[\s\S]*openCreateRealCutAction\(\)/);
+  assert.match(clickActions, /name === "open-create-assistant"[\s\S]*const project = getSelectedProject\(\)/);
+  assert.match(clickActions, /name === "open-create-assistant"[\s\S]*runDirectWorkbenchAction\("create-assistant"/);
+  assert.match(clickActions, /name === "open-create-assistant"[\s\S]*openCreateAssistantAction\(\)/);
 });
 
 test("main agent landing notices expose a compact mobile follow-up strip", () => {