- Replace custom Observable protocol and @Published with Apple's @Observable macro
- Add withObservationTracking in renderToBuffer for automatic per-property dependency tracking
- Add type-based @Environment(Type.self) and .environment(object) for observable objects
- Add ObjectEnvironmentModifier for injecting observable objects into the environment
- Add needsCacheClear flag to AppState for thread-safe cache invalidation
- Add cross-platform test script (scripts/test-linux.sh) for Docker-based Linux verification
- Add DemoAppHeader with system info display (OS, version, architecture)
- Consolidate Example App: extract ImageDemoHelpers, KeyboardHelpSection, ValueDisplayRow
- Add pre-push verification rule to CLAUDE.md
- Verified on both macOS and Linux (swift:6.0 container), 1155 tests passing
AppHeader is rendered at the top of the terminal by RenderLoop, similar to
StatusBar at the bottom. Views declare header content via .appHeader { }
ViewBuilder modifier. Supports standard (thin divider) and block (half-block
with appHeaderBackground) appearance. Hidden when no content is set.
Diff cache invalidates on header height changes to prevent ghosting.
Update IDETemplateMacros.plist and replace headers in 136 Swift files with
new format: 🖥️ TUIKit — Terminal UI Kit for Swift. Remove sdsd.swift template draft.
phranck