feat: add single-instance support, Android APK download, and splash screen styling

packages/desktop/src-tauri/Cargo.lock

@@ -2645,6 +2645,7 @@ dependencies = [
  "tauri-plugin-log",
  "tauri-plugin-notification",
  "tauri-plugin-opener",
+ "tauri-plugin-single-instance",
  "tauri-plugin-updater",
  "tauri-plugin-websocket",
  "tokio",
@@ -4299,6 +4300,21 @@ dependencies = [
  "zbus",
 ]
 
+[[package]]
+name = "tauri-plugin-single-instance"
+version = "2.3.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "acba6b5ca527a96cdfcc96ae09b09ccb91ddff5e33978ca6873b96ea16bb404c"
+dependencies = [
+ "serde",
+ "serde_json",
+ "tauri",
+ "thiserror 2.0.18",
+ "tracing",
+ "windows-sys 0.60.2",
+ "zbus",
+]
+
 [[package]]
 name = "tauri-plugin-updater"
 version = "2.9.0"