CHANGES(docs): note sphinx autodoc fixes

why: Document the sphinx-autodoc-typehints configuration changes
that fix "Unexpected indentation" errors in documentation build
what:
- Add Documentation section to v1.49.x unreleased
- Note the param/rtype injection and forward reference fixes

Author: tony

CHANGES

@@ -31,6 +31,15 @@ $ uvx --from 'vcspull' --prerelease allow vcspull
 
 <!-- Maintainers, insert changes / features for the next release here -->
 
+### Documentation
+
+#### Fix Sphinx autodoc indentation errors (#490)
+
+- Configure `sphinx-autodoc-typehints` to prevent RST parsing conflicts with
+  Napoleon-processed docstrings by disabling type injection into docstring
+  bodies (`always_document_param_types`, `typehints_document_rtype`).
+- Suppress cosmetic forward reference warnings from TYPE_CHECKING imports.
+
 _Upcoming changes will be written here._
 
 ## vcspull v1.48.0 (2025-11-30)