feat(k-ui): first slice: App trait + run loop, builders (column/row/text/button), flex layout, theme tokens (Whimsy Dark), tiny-skia + fontdue render (Noto Sans Latin subset), keyboard focus ring; tally demo; manifest memory key (pm spawns with it)

crates/k-ui/src/lib.rs

@@ -0,0 +1,25 @@
+//! K-UI (see the vision's K-UI note): an app says what its UI is, as a
+//! pure function of its state; K-UI lays it out, draws it in the theme,
+//! and handles focus and keys. It runs inside the app and draws into the
+//! app's window.
+
+#![no_std]
+#![forbid(unsafe_code)]
+
+extern crate alloc;
+
+pub mod element;
+pub mod layout;
+pub mod render;
+pub mod run;
+pub mod text;
+pub mod theme;
+pub mod ui;
+
+pub use element::{Element, Size, button, column, row, text};
+pub use run::run;
+pub use theme::{ButtonVariant, Spacing, TextColour, TextStyle};
+pub use ui::App;
+
+#[cfg(test)]
+mod tests;