Filter model selector by API keys and add user-facing documentation

- Model selector now only shows models with configured API keys
- Added yellow hint in model selector UI explaining the filtering
- Updated README.md to document the filtering behavior in both API Keys and /model sections
- Bumped version to 0.7.11

packages/coding-agent/CHANGELOG.md

@@ -2,6 +2,12 @@
 
 ## [Unreleased]
 
+## [0.7.11] - 2025-11-16
+
+### Changed
+
+- The `/model` selector now filters models based on available API keys. Only models for which API keys are configured in environment variables are shown. This prevents selecting models that would fail due to missing credentials. A yellow hint is displayed at the top of the selector explaining this behavior. ([#19](https://github.com/badlogic/pi-mono/pull/19))
+
 ## [0.7.10] - 2025-11-14
 
 ### Added