feat(08-03): integrate proxy, delay, and retry into ZhihuCrawler

- Add CrawlerConfig with ProxyConfig, delay, and retry settings
- Integrate proxy configuration via _start_browser_with_proxy()
- Add random delay via _apply_random_delay()
- Add retry logic via _crawl_with_retry using tenacity
- Add ZhihuApiInterceptor tests for x-zse-96 handling
- All tests pass

tests/test_crawler/test_api_intercept.py

@@ -0,0 +1,78 @@
+"""Tests for API Interception and x-zse-96 Signature Handling"""
+
+import pytest
+from unittest.mock import Mock
+
+from kb_workflow.crawler.zhihu_crawler import ZhihuApiInterceptor
+
+
+class TestApiIntercept:
+    """Tests for API interception and x-zse-96 signature handling."""
+
+    def test_intercept_answer_api(self):
+        """Intercept answer API and capture response data."""
+        interceptor = ZhihuApiInterceptor()
+
+        # Mock route object
+        route = Mock()
+        route.request.url = "https://www.zhihu.com/api/v4/answers/12345"
+
+        mock_response = Mock()
+        mock_response.json.return_value = {"id": 12345, "content": "test answer content"}
+        route.fetch.return_value = mock_response
+
+        interceptor.handle_route(route)
+
+        assert "answer" in interceptor.captured_data
+        assert interceptor.captured_data["answer"]["id"] == 12345
+
+    def test_intercept_article_api(self):
+        """Intercept article API and capture response data."""
+        interceptor = ZhihuApiInterceptor()
+
+        route = Mock()
+        route.request.url = "https://zhuanlan.zhihu.com/api/v4/articles/67890"
+
+        mock_response = Mock()
+        mock_response.json.return_value = {"id": 67890, "title": "test article"}
+        route.fetch.return_value = mock_response
+
+        interceptor.handle_route(route)
+
+        assert "article" in interceptor.captured_data
+        assert interceptor.captured_data["article"]["id"] == 67890
+
+    def test_non_api_requests_continue(self):
+        """Non-API requests continue normally."""
+        interceptor = ZhihuApiInterceptor()
+
+        route = Mock()
+        route.request.url = "https://www.zhihu.com/static/some.js"
+
+        interceptor.handle_route(route)
+
+        # Should call continue_ for non-API requests
+        route.continue_.assert_called_once()
+        route.fulfill.assert_not_called()
+
+    def test_x_zse_96_auto_handled(self):
+        """x-zse-96 signature is automatically handled by browser via route.fetch().
+
+        The interceptor automatically uses the browser's fetch() which includes
+        the x-zse-96 signature headers generated by the browser context.
+        """
+        interceptor = ZhihuApiInterceptor()
+
+        route = Mock()
+        route.request.url = "https://www.zhihu.com/api/v4/answers/123"
+
+        mock_response = Mock()
+        mock_response.json.return_value = {"id": 123, "signed": True}
+        route.fetch.return_value = mock_response
+
+        interceptor.handle_route(route)
+
+        # fetch() is called (which would include browser-generated x-zse-96)
+        route.fetch.assert_called_once()
+        # fulfill() returns response to page
+        route.fulfill.assert_called_once()