docs/conf.py(fix): disable rtype injection for autodoc

why: Injected :rtype: fields cause RST parsing conflicts with
Napoleon-processed docstrings
what:
- Set typehints_document_rtype = False
- Ensures all type hints appear in signature only, not docstring body

Author: tony

docs/conf.py

@@ -123,6 +123,8 @@
 # When autodoc_typehints = "signature", disable parameter type injection
 # to prevent RST indentation conflicts with Napoleon-processed docstrings
 always_document_param_types = False
+# Disable return type injection in docstrings (types shown in signature only)
+typehints_document_rtype = False
 
 # sphinx.ext.napoleon
 napoleon_google_docstring = True