Bump minimum Python version to 3.10

Generated code uses PEP 604 union syntax (str | None) via ruff UP rules.
No from __future__ import annotations in generated files, so 3.9 would
fail at runtime. CI test matrix already starts at 3.10.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: kwent

CHANGELOG.md

@@ -33,15 +33,15 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
 - Regenerated client from latest OpenAPI specification
 - **BREAKING**: Catalog Fields renamed to Catalog Properties across all endpoints and models
-- Minimum Python version bumped to 3.10 in generated code (SDK still supports 3.9 via pyproject.toml)
+- **BREAKING**: Minimum Python version bumped to 3.10
 
 ### Removed
 - Catalog Fields endpoints and models (replaced by Catalog Properties)
 - Some escalation policy path rule type models (consolidated in upstream spec)
 
 ### Fixed
 - Applied nullable enum fix to 1,348 model files via `tools/fix_nullable_enums.py`
-- Escalation path endpoints now fully generated — added `tools/fix_openapi_escalation_paths.py` to patch inline `oneOf` variants into named `$ref` schemas and fix missing array `items` definitions
+- Escalation path endpoints now fully generated — added `tools/fix_openapi_escalation_paths.py` to patch inline `oneOf` variants into named `$ref` schemas ([upstream bug](https://github.com/openapi-generators/openapi-python-client/issues/1428))
 
 ## [1.2.1] - 2025-03-02
 

pyproject.toml

@@ -10,7 +10,7 @@ packages = [
 include = ["CHANGELOG.md", "rootly_sdk/py.typed"]
 
 [tool.poetry.dependencies]
-python = "^3.9"
+python = "^3.10"
 httpx = ">=0.20.0,<0.29.0"
 attrs = ">=22.2.0"
 python-dateutil = "^2.8.0"