Cap pydantic-ai dependency to <2 to fix clean-install ImportError

Released 0.11.0 declared an unbounded `pydantic-ai>=1.99.0`. A fresh
resolve (no lockfile) selected pydantic-ai 2.x, which removed
`pydantic_ai.mcp.MCPServer`, so freeact crashed on import with
`ImportError: cannot import name 'MCPServer'`. The source repo only
worked because uv.lock pinned 1.99.0.

Constrain to `>=1.99.0,<2` and refresh uv.lock. A clean resolve now
stays on the 1.x line and freeact imports and runs.

Fixes #106

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: krasserm

pyproject.toml

@@ -11,7 +11,7 @@ license = "Apache-2.0"
 dependencies = [
     "aiostream>=0.7.1",
     "google-genai>=2.4.0",
-    "pydantic-ai>=1.99.0",
+    "pydantic-ai>=1.99.0,<2",
     "python-dotenv>=1.0.0",
     "pillow>=12.0.0",
     "pyyaml>=6.0.3",