Pi 0.37.5

Added

• ExtensionAPI: setModel(), getThinkingLevel(), setThinkingLevel() methods for extensions to change model and thinking level at runtime (#509)
• Exported truncation utilities for custom tools: truncateHead, truncateTail, truncateLine, formatSize, DEFAULT_MAX_BYTES, DEFAULT_MAX_LINES, TruncationOptions, TruncationResult
• New example truncated-tool.ts demonstrating proper output truncation with custom rendering for extensions
• New example preset.ts demonstrating preset configurations with model/thinking/tools switching (#347)
• Documentation for output truncation best practices in docs/extensions.md
• Exported all UI components for extensions: ArminComponent, AssistantMessageComponent, BashExecutionComponent, BorderedLoader, BranchSummaryMessageComponent, CompactionSummaryMessageComponent, CustomEditor, CustomMessageComponent, DynamicBorder, ExtensionEditorComponent, ExtensionInputComponent, ExtensionSelectorComponent, FooterComponent, LoginDialogComponent, ModelSelectorComponent, OAuthSelectorComponent, SessionSelectorComponent, SettingsSelectorComponent, ShowImagesSelectorComponent, ThemeSelectorComponent, ThinkingSelectorComponent, ToolExecutionComponent, TreeSelectorComponent, UserMessageComponent, UserMessageSelectorComponent, plus utilities renderDiff, truncateToVisualLines
• docs/tui.md: Common Patterns section with copy-paste code for SelectList, BorderedLoader, SettingsList, setStatus, setWidget, setFooter
• docs/tui.md: Key Rules section documenting critical patterns for extension UI development
• docs/extensions.md: Exhaustive example links for all ExtensionAPI methods and events
• System prompt now references docs/tui.md for TUI component development