add SPA config UI, wire media/rss adapters, event-driven layout push

- React SPA: dashboard, data sources CRUD, widgets CRUD, layout builder,
  presets. TanStack Router + Query, shadcn/ui, Vite proxy to :3000
- wire media + rss adapters into polling loop, remove xtb source type
- media adapter: read username/password from headers, proper subsonic auth
- event handler: subscribe to LayoutChanged, push screen update to clients
- fix clippy warnings across workspace (Default impls, collapsible ifs,
  redundant closures, is_none_or, unused imports)

crates/client-desktop/src/main.rs

@@ -1,11 +1,11 @@
-use std::thread;
-use std::sync::mpsc;
-use std::time::Duration;
-use client_domain::{BoundingBox, DisplayPort, NetworkPort};
 use client_application::ClientApp;
-use tcp_client::StdTcpClient;
+use client_domain::{BoundingBox, DisplayPort, NetworkPort};
 use display_terminal::TerminalDisplay;
 use protocol::decode_server_message;
+use std::sync::mpsc;
+use std::thread;
+use std::time::Duration;
+use tcp_client::StdTcpClient;
 
 fn main() {
     let screen = BoundingBox::screen(240, 320);
@@ -35,12 +35,12 @@ fn main() {
             }
 
             match net.receive() {
-                Ok(Some(payload)) => {
-                    match decode_server_message(&payload) {
-                        Ok(msg) => { let _ = tx.send(msg); }
-                        Err(e) => println!("[NET] Decode error: {e}"),
+                Ok(Some(payload)) => match decode_server_message(&payload) {
+                    Ok(msg) => {
+                        let _ = tx.send(msg);
                     }
-                }
+                    Err(e) => println!("[NET] Decode error: {e}"),
+                },
                 Ok(None) => {
                     thread::sleep(Duration::from_millis(50));
                 }
@@ -67,11 +67,14 @@ fn main() {
 
                         for kv in &cmd.state.data {
                             if let protocol::WireValue::String(s) = &kv.value {
-                                display.draw_text(
-                                    &format!("{}: {s}", kv.key),
-                                    cmd.bounds.x, cmd.bounds.y,
-                                    cmd.bounds,
-                                ).unwrap();
+                                display
+                                    .draw_text(
+                                        &format!("{}: {s}", kv.key),
+                                        cmd.bounds.x,
+                                        cmd.bounds.y,
+                                        cmd.bounds,
+                                    )
+                                    .unwrap();
                             }
                         }
                     }