refactor: 移除模板变量 {{change-name}} 替换功能，模板改为纯静态文本

tests/core/assembler.test.ts

@@ -56,9 +56,10 @@ describe("assemblePlanPrompt", () => {
     expect(prompt).not.toContain("# 已有设计");
   });
 
-  it("替换模板中的 {{change-name}}", async () => {
+  it("包含格式模板（纯静态文本）", async () => {
     const prompt = await assemblePlanPrompt(defaultConfig, TMP_DIR, "user-auth", "design");
-    expect(prompt).toContain("user-auth 设计文档");
+    expect(prompt).toContain("格式模板");
+    expect(prompt).toContain("# 设计文档");
     expect(prompt).not.toContain("{{change-name}}");
   });
 
@@ -110,7 +111,7 @@ describe("assemblePlanPrompt", () => {
             {
               name: "spec",
               prompt: "生成规格",
-              template: "# {{change-name}} 规格",
+              template: "# 规格文档",
             },
           ],
         },
@@ -118,7 +119,7 @@ describe("assemblePlanPrompt", () => {
     };
     const prompt = await assemblePlanPrompt(config, TMP_DIR, "my-feature", "spec");
     expect(prompt).toContain("spec");
-    expect(prompt).toContain("my-feature 规格");
+    expect(prompt).toContain("规格文档");
     expect(prompt).not.toContain("design");
   });
 });