theme config, layout preview, container alignment

Server: ThemeConfig entity + CRUD (GET/PUT /theme), SQLite persistence,
ThemeUpdate broadcast to ESP32 on save and initial connect.
Client: render engine uses theme colors, full-screen redraw on theme change.
SPA: theme page with color pickers + presets, layout preview with TS port
of layout engine, justify/align controls on containers.
DisplayHint refactored to struct (kind + h_align + v_align).

crates/client-desktop/src/main.rs

@@ -1,4 +1,5 @@
 use client_application::ClientApp;
+use client_domain::NetworkPort;
 use client_domain::{BoundingBox, DisplayPort, FontMetrics, RenderEngine, ThemeConfig};
 use display_terminal::TerminalDisplay;
 use domain::DisplayHint;
@@ -7,7 +8,6 @@ use std::sync::mpsc;
 use std::thread;
 use std::time::Duration;
 use tcp_client::StdTcpClient;
-use client_domain::NetworkPort;
 
 fn main() {
     let screen = BoundingBox::screen(240, 320);
@@ -78,14 +78,18 @@ fn main() {
                         display.fill_rect(cmd.bounds, bg).unwrap();
 
                         let hint: DisplayHint = cmd.display_hint.clone().into();
-                        let data: Vec<(String, domain::Value)> = cmd.state.data
+                        let data: Vec<(String, domain::Value)> = cmd
+                            .state
+                            .data
                             .iter()
                             .map(|kv| (kv.key.clone(), kv.value.clone().into()))
                             .collect();
 
                         let draw_cmds = engine.render_widget(&hint, &data, cmd.bounds, 0);
                         for dc in &draw_cmds {
-                            display.draw_text_span(&dc.text, dc.x, dc.y, dc.color, dc.font).unwrap();
+                            display
+                                .draw_text_span(&dc.text, dc.x, dc.y, dc.color, dc.font)
+                                .unwrap();
                         }
                     }
                     display.flush().unwrap();