Release v2.2.0 - December 2025 Home Assistant modernization

- Modernize to Home Assistant 2025.12 standards
- Update Python 3.13+ type hints and async patterns
- Add comprehensive test suite
- Add diagnostics support
- Require Home Assistant 2025.12.0+

Author: rsnodgrass

custom_components/poolmath/manifest.json

@@ -4,9 +4,10 @@
   "codeowners": ["@rsnodgrass"],
   "config_flow": true,
   "documentation": "https://github.com/rsnodgrass/hass-poolmath",
+  "homeassistant": "2025.12.0",
   "integration_type": "service",
   "iot_class": "cloud_polling",
   "issue_tracker": "https://github.com/rsnodgrass/hass-poolmath/issues",
   "requirements": ["aiohttp>=3.10.0"],
-  "version": "2.1.0"
+  "version": "2.2.0"
 }