- 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
- Add @Environment<Value> property wrapper for declarative environment access
- Add StateRegistration.activeEnvironment for ambient context during body evaluation
- Set/restore activeEnvironment in renderToBuffer() and RenderLoop.render()
- Refactor RenderLoop.render() into focused helpers to fix function_body_length warning
- Add 7 tests covering default values, active environment, dynamic reads, and propagation
phranck