refactor extract_section_content to improve section handling logic

tools/search_md.py

@@ -284,18 +284,18 @@ def extract_section_content(content: str, section_type: str) -> str:
         return ""
         
     for line in lines:
-        if pattern.match(line):
-            in_section = True
-            section_level = len(line) - len(line.lstrip('#'))
-            continue
-            
         if in_section:
             if line.startswith('#'):
                 current_level = len(line) - len(line.lstrip('#'))
                 if current_level <= section_level:
                     in_section = False
-                    continue
-            section_content.append(line)
+                else:
+                    section_content.append(line)
+            else:
+                section_content.append(line)
+        elif pattern.match(line):
+            in_section = True
+            section_level = len(line) - len(line.lstrip('#'))
             
     return '\n'.join(section_content)