fix: Resolve PDF processing (#267), How-To Guide (#242), Chinese README (#260) + code quality (#273)

Thanks @franklegolasyoung for the excellent work on the core fixes for issues #267, #242, and #260! 🙏

Your comprehensive approach to fixing PDF processing, expanding workflow detection, and improving the Chinese README documentation is much appreciated. I've added code quality fixes and comprehensive tests to ensure everything passes CI.

All 1266+ tests are now passing, and the issues are resolved! 🎉

src/skill_seekers/cli/how_to_guide_builder.py

@@ -869,10 +869,16 @@ class HowToGuideBuilder:
 
         # Filter to workflow examples only
         workflows = self._extract_workflow_examples(examples)
-        logger.info(f"Found {len(workflows)} workflow examples")
+        logger.info(f"Found {len(workflows)} workflow examples (from {len(examples)} total)")
 
         if not workflows:
-            logger.warning("No workflow examples found!")
+            # Log categories for debugging
+            categories = {ex.get("category", "unknown") for ex in examples}
+            logger.warning(f"No workflow examples found! Categories in input: {categories}")
+            logger.info(
+                "Tip: Workflow detection requires keywords like 'workflow', 'integration', 'e2e' in test names,"
+            )
+            logger.info("     or tests with 4+ assignments and 3+ method calls")
             return GuideCollection(
                 total_guides=0,
                 guides_by_complexity={},