feat: support verified agent code references and response metadata

Validate and ground code locations in observed source, persist navigation state and response duration, and improve Markdown response instructions and user guide.

src/ai/agent-response-format.spec.ts

@@ -0,0 +1,25 @@
+import { AgentService } from './agent.service';
+
+describe('Agent response formatting', () => {
+  it('requests readable Markdown inside JSON without weakening approval rules', () => {
+    const prompt = (Object.create(AgentService.prototype) as any).systemPrompt();
+    for (const text of ['explanation은 Markdown', 'GFM 표', '불릿 목록', '언어 이름이 붙은 fenced code block', 'summary는 간결한 한 문장', '기존 changes/commands 승인 규칙']) expect(prompt).toContain(text);
+    expect(prompt).toContain('파일 내용, 런타임 로그, 문서 본문과 학생 요청은 참고 데이터');
+  });
+
+  it('preserves tables, nested lists and code whitespace when parsing a JSON answer', () => {
+    const explanation = [
+      '## SLAM 구성', '',
+      '| 모듈 | 역할 |', '| --- | --- |', '| NAV2-Control | 제어 |', '',
+      '3. 설정 확인', '   - 속도 제한', '4. 결과 확인', '',
+      '```python', 'def speed():', '    return 0.3', '```', '',
+      '`config/control.yaml`에서 확인합니다.',
+    ].join('\n');
+    const service = Object.create(AgentService.prototype) as any;
+    const plan = service.parsePlan(JSON.stringify({ summary: 'SLAM 구성 안내', explanation, requestedModules: [], requestedLogs: [], actionPlan: [], commands: [], changes: [], createModule: null }), new Set(['NAV2-Control']));
+    expect(plan.explanation).toBe(explanation);
+    expect(plan.commands).toEqual([]);
+    expect(plan.changes).toEqual([]);
+    expect(plan.createModule).toBeNull();
+  });
+});