feat: add Python 3.10 support

- Lower requires-python from >=3.11 to >=3.10 (aligns with pydantic-ai)
- Add 3.10 to CI test matrix
- Use asyncio.TimeoutError with noqa for ruff UP041 (TimeoutError is not
  an alias for asyncio.TimeoutError until 3.11)
- Update ruff target-version to py310
- Update README and classifiers

The codebase already uses `from __future__ import annotations` everywhere,
so PEP 604 union syntax and lowercase generics work on 3.10. No other
3.11-only features are used (no match/case, ExceptionGroup, TaskGroup,
tomllib, StrEnum, or Self).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: patrick-chinchill

.github/workflows/test.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ["3.11", "3.12", "3.13"]
+        python-version: ["3.10", "3.11", "3.12", "3.13"]
     steps:
       - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5  # v4.2.2
       - uses: astral-sh/setup-uv@e4db8464a088ece1b920f60402e813ea4de65b8f  # v4

README.md

@@ -66,7 +66,7 @@ async def handle_mention(thread, message):
 | Feature | chat-sdk | Raw platform SDKs | BotFramework SDK |
 |---------|----------|--------------------|------------------|
 | Multi-platform from one codebase | 8 platforms | 1 per SDK | Teams + limited |
-| Async-native (Python 3.11+) | Yes | Varies | No |
+| Async-native (Python 3.10+) | Yes | Varies | No |
 | Cross-platform cards | Card model | Platform-specific | Adaptive Cards only |
 | Thread locking / dedup | Built-in | DIY | DIY |
 | State abstraction (mem/redis/pg) | Built-in | DIY | DIY |

pyproject.toml

@@ -4,14 +4,15 @@ version = "0.0.1a11"
 description = "Multi-platform async chat SDK for Python — port of Vercel Chat"
 readme = "README.md"
 license = {text = "MIT"}
-requires-python = ">=3.11"
+requires-python = ">=3.10"
 dependencies = []
 classifiers = [
     "Development Status :: 3 - Alpha",
     "Framework :: AsyncIO",
     "Intended Audience :: Developers",
     "License :: OSI Approved :: MIT License",
     "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",
     "Programming Language :: Python :: 3.13",
@@ -58,7 +59,7 @@ packages = ["src/chat_sdk"]
 asyncio_mode = "auto"
 
 [tool.ruff]
-target-version = "py311"
+target-version = "py310"
 line-length = 120
 
 [tool.ruff.lint]

src/chat_sdk/thread.py

@@ -579,7 +579,7 @@ async def _edit_loop() -> None:
                 try:
                     await asyncio.wait_for(stop_event.wait(), timeout=interval_s)
                     break  # stop was signaled
-                except asyncio.TimeoutError:
+                except asyncio.TimeoutError:  # noqa: UP041 — support Python 3.10
                     pass  # interval elapsed, do the edit
                 if stop_event.is_set() or msg is None:
                     break