migrate ui components to gpui-kit

docs/native-theme-migration.md

@@ -1,5 +1,17 @@
 # Migrate the UI to GPUI-Kit, then native-theme
 
+> **Status: Phase A is implemented** (on the working tree, uncommitted). The
+> app builds against `gpui-kit` (resolved 0.7.3 / gpui-pre 0.3.9), every UI
+> element comes from the kit, `crates/theme` is deleted, and `crates/ui` is a
+> utilities-only crate (`motion`, `typography`, `layout`, `styled` helpers,
+> `window_drag`). Two planned holdouts moved into app crates instead of being
+> reimplemented on kit parts: the chat message composition (→ `chat_ui::message`)
+> and the sidebar `Nav` row (→ `workspace::nav`). The panel-background-image
+> feature was dropped (per §8). Validation: `cargo check`, `cargo clippy` and
+> `cargo fmt` are clean workspace-wide, the desktop binary builds, and `ui`,
+> `workspace` compile for `wasm32-unknown-unknown` (the remaining web failures
+> are the pre-existing `auto_update` → `rustls` chain, present at HEAD).
+
 Plan to move coop's custom UI elements onto [GPUI-Kit](https://gpui-kit.com)
 (`gpui-kit` 0.7.1), delete the custom theme implementation (`crates/theme`),
 and then integrate [`native-theme`](https://github.com/tiborgats/native-theme)