v0.26.7: Directory-specific sessions, MCP image support, and Gemini fixes

New features

- Directory-Specific Sessions - Sessions are now stored per directory and automatically switch to the correct working directory when loaded. The /sessions command shows only sessions created in your current directory plus favorited sessions
- MCP Image Support - MCP tools can now return images that are sent to the LLM for analysis
- Custom Models for Subdroids - Subdroids can now use custom models instead of inheriting from parent session

Bug fixes

- Fixed console output issues in exec mode
- Fixed spec mode for Gemini models
- Fixed exit spec mode prompt behavior