Defines `ControlTokenSet`, a generic container for design tokens (colors, fonts, shadows) that maps token keys to theme values. Supports per-control overrides and theme-wide overrides. This is the core of the theming system and could be extracted as a standalone library for any UIKit/SwiftUI project needing a flexible token-based theming solution.

A small, self-contained utility that synchronizes `CABasicAnimation` instances across multiple views by sharing a common `beginTime`. Useful for shimmer effects or any coordinated animation. Demonstrates a clean, reusable pattern for animation synchronization without external dependencies.

Defines the `Obscurable` protocol and provides `BlurringView` and `DimmingView` implementations. This pattern allows any view to be used as a modal background with blur or dim effects. The protocol is minimal and the implementations are self-contained, making it easy to reuse in other projects for custom modal presentations.

A custom `UIPresentationController` that implements a drawer-style presentation (top, bottom, left, right) with shadow, dimming, and keyboard-aware resizing. Handles interactive dismissal and expansion. This is a complex, well-crafted component that could be extracted and used in any UIKit app needing a flexible drawer.

A reusable bottom sheet controller with collapsed/expanded states, resizing handle, dimming view, and spring animations. Uses `UIViewPropertyAnimator` and `UISpringTimingParameters` for smooth transitions. The rubber-banding and expansion logic are well-implemented and isolated, making this a strong candidate for extraction into a standalone bottom sheet library.

A reusable calendar grid view with a custom `UICollectionViewLayout` and data source protocol. Supports single/multiple selection, date ranges, and various cell types (day, month, year). The layout and data source are decoupled, allowing reuse in any calendar or grid-based component. Demonstrates advanced collection view customization.