Support Claude agent SDK-style structured outputs in the OpenCode SDK

Improvements

• CoreSupport custom API URL per model
• CoreAdd automatic variant generation for Venice models@dpuyosa
• CoreUse Promise.all for MCP listTools calls to improve performance
• CoreUpgrade OpenTUI to version 0.1.79
• CoreImprove compaction check logic
• CoreMake read tool offset 1-indexed to match line numbers and avoid confusion
• CoreAdd directory reading capability to the read tool
• TerminalUse FFI to resolve Windows raw input and Ctrl+C handling issues@Hona
• TerminalAdd toggle to hide session header in TUI@kitlangton
• DesktopGuard randomUUID in insecure browser contexts
• DesktopWorkspace reset functionality fixed@neriousy