Add xhigh thinking level for OpenAI codex-max models

- Add 'xhigh' to ThinkingLevel type in ai and agent packages
- Map xhigh to reasoning_effort: 'max' for OpenAI providers
- Add thinkingXhigh color token to theme schema and built-in themes
- Show xhigh option only when using codex-max models
- Update CHANGELOG for both ai and coding-agent packages

closes #143

packages/ai/package.json

@@ -20,13 +20,13 @@
 		"prepublishOnly": "npm run clean && npm run build"
 	},
 	"dependencies": {
-		"@anthropic-ai/sdk": "^0.61.0",
-		"@google/genai": "^1.30.0",
+		"@anthropic-ai/sdk": "0.71.2",
+		"@google/genai": "1.31.0",
 		"@sinclair/typebox": "^0.34.41",
 		"ajv": "^8.17.1",
 		"ajv-formats": "^3.0.1",
 		"chalk": "^5.6.2",
-		"openai": "5.21.0",
+		"openai": "6.10.0",
 		"partial-json": "^0.1.7",
 		"zod-to-json-schema": "^3.24.6"
 	},