* Bump ty to >=0.0.1a25 with type fixes
Follow-up to #2295. Updates ty and fixes compatibility issues with alpha 25, including:
- Updated ignore comment syntax (possibly-unbound-attribute → possibly-missing-attribute)
- Fixed async generator type handling with anext()
- Fixed type narrowing for timeout parameters
- Converted base_url assignments to AnyHttpUrl after string manipulation
- Added CallToolResult to return type annotations
- Removed redundant type casts
- Fixed test form data to use strings instead of bytes
ty alpha 25 has limitations with isinstance() narrowing on unions (see pyproject.toml for details), requiring some targeted type ignores.
* Pin ty to ==0.0.1a25
Alpha releases can have breaking changes, so pin to the tested version.
