Add dynamic UI theme for server browser

Introduce runtime-driven UI theming for the server browser

- Expose PushUITheme() in F4TServerBrowserBridge and implement ColorToJson + PushUIThemeInternal to serialize HUD colors and invoke a JS hook.
- Call PushUITheme on UI initialization and when the browser is shown so the webview receives current HUD colors.
- Add frontend handler for "uiTheme" in app.js and a new components/theme.js that implements window.applyCoTheme to set CSS vars and tint the cursor SVG.
- Update styles.css to use RGB component CSS variables (--co-r/--co-g/--co-b and background equivalents) so colors can be overridden at runtime.
- Update index.html to include the new theme script and tweak cursor SVG stroke width; cursor asset updated as well.

This enables the plugin to synchronize the in-game HUD colors with the browser UI dynamically.

plugin/src/F4TPrismaUI.cpp

@@ -178,6 +178,7 @@ namespace F4T::PrismaUI
 				});
 
 			F4T::ServerBrowser::ServerBrowserBridge::Initialize(g_api, a_view);
+			F4T::ServerBrowser::ServerBrowserBridge::PushUITheme();
 
 			g_api->BindUIEvent(a_view, "coAction", [](const char* a_json) {
 				if (!a_json) {

plugin/src/F4TServerBrowserBridge.cpp

@@ -5,6 +5,7 @@
 #include "F4TServerBrowserBridge.h"
 #include "F4TServerBrowserData.h"
 
+#include <algorithm>
 #include <format>
 #include <string_view>
 
@@ -58,6 +59,38 @@ namespace F4T::ServerBrowser
 			});
 		}
 
+		nlohmann::json ColorToJson(const RE::NiColor& a_color)
+		{
+			const auto toByte = [](float a_channel) {
+				return static_cast<int>(std::clamp(a_channel * 255.0f, 0.0f, 255.0f));
+			};
+
+			return nlohmann::json{
+				{ "r", toByte(a_color.r) },
+				{ "g", toByte(a_color.g) },
+				{ "b", toByte(a_color.b) }
+			};
+		}
+
+		void PushUIThemeInternal()
+		{
+			if (!g_api || g_view == 0 || !g_api->IsValid(g_view)) {
+				return;
+			}
+
+			const auto hudColor = RE::HUDMenuUtils::GetGameplayHUDColor();
+			const auto hudBgColor = RE::HUDMenuUtils::GetGameplayHUDBackgroundColor();
+			const auto themePayload = nlohmann::json{
+				{ "hud", ColorToJson(hudColor) },
+				{ "hudBackground", ColorToJson(hudBgColor) }
+			};
+
+			const auto script = std::format(
+				"if(window.applyCoTheme){{window.applyCoTheme({});}}",
+				themePayload.dump());
+			g_api->Invoke(g_view, script.c_str());
+		}
+
 		void PushConnectionStatusEvent()
 		{
 			const auto connected = F4T::Networking::IsConnectedToServer();
@@ -136,6 +169,7 @@ namespace F4T::ServerBrowser
 
 	void ServerBrowserBridge::OnBrowserShown()
 	{
+		PushUIThemeInternal();
 		DispatchEvent(nlohmann::json{ { "type", "menuOpened" } });
 		RefreshServerList();
 	}
@@ -289,4 +323,9 @@ namespace F4T::ServerBrowser
 	{
 		PushConnectionStatusEvent();
 	}
+
+	void ServerBrowserBridge::PushUITheme()
+	{
+		PushUIThemeInternal();
+	}
 }