Embed server browser as main menu modal

Refactors the browser UI into a reusable `CO_Browser.create()` module and adds embedded modal styling so MULTIPLAYER opens inside the main menu instead of swapping to a separate view. Updates main-menu JS/CSS to host, animate, and route input for the browser panel while keeping nav and prompts in sync. On the C++ side, PrismaUI now drives browser show/hide and event dispatch through the main menu view, and `ServerBrowserBridge::SetView()` was added so bridge events target the active host view.

plugin/include/F4TServerBrowserBridge.h

@@ -10,6 +10,7 @@ namespace F4T::ServerBrowser
 	{
 	public:
 		static void Initialize(PRISMA_UI_API::IVPrismaUI4* a_api, PrismaView a_view);
+		static void SetView(PrismaView a_view);
 		static void OnBrowserShown();
 		static void OnBrowserHidden();
 		static void HandleAction(const nlohmann::json& a_action);