feat(qbz-slint): per-device-type icons in the QConnect device picker

Mirror Qobuz Connect's device icons in the connect flyout: map each renderer's
device_type to an icon (6 -> smartphone, 5 -> monitor or globe when the name is a
web player/browser, else -> speaker), matching the Tauri QconnectBadge
resolveDeviceType. Adds lucide monitor/smartphone/speaker/globe svgs, an icon key
on the QconnectDevice model computed in the event sink, and a per-row icon in the
PlayerBar device list.

cc

crates/qbz-slint/ui/state.slint

@@ -1984,6 +1984,8 @@ export struct QconnectDevice {
     name: string,
     is-local: bool,     // this is QBZ itself ("Play here")
     is-active: bool,    // currently the active renderer
+    // Device-type icon key (mirrors Qobuz Connect): "computer" | "web" | "mobile" | "speaker".
+    icon: string,
 }
 
 // Qobuz Connect DEV diagnostics — live session topology + a rolling event log,