add all crates: domain, protocol, application, client, adapters, ESP32 firmware

Server: domain (entities, value objects, ports), protocol (postcard wire types),
application (config service, data projection), adapters (config-memory, tcp-server),
bootstrap (composition root with fake data).

Client: client-domain (layout engine, render tree, HAL ports),
client-application (message handling, repaint commands),
adapters (tcp-client, display-terminal), client-desktop (end-to-end working).

ESP32: client-esp32 firmware with ILI9341 display over SPI, WiFi networking.
Display test verified on hardware — landscape orientation, text rendering works.

60 workspace tests, all passing.

crates/client-domain/src/lib.rs

@@ -0,0 +1,9 @@
+mod bounding_box;
+mod layout_engine;
+mod render_tree;
+pub mod ports;
+
+pub use bounding_box::BoundingBox;
+pub use layout_engine::LayoutEngine;
+pub use render_tree::RenderTree;
+pub use ports::{DisplayPort, NetworkPort, StoragePort, ClientConfig};