Add hover sync and CO hover component

Add a hover system to restore :hover-like behavior for custom UI elements in the CommonwealthOnline view. Changes include:

- plugin/src/F4TPrismaUI.cpp: add SyncBrowserHover() which reads the native cursor position, converts it to client coordinates, and invokes a JS update on the server browser view; register a periodic task to call SyncBrowserHover every other tick.
- ui/views/CommonwealthOnline/browser/components/hover.js: new component that tracks pointer position, determines hovered targets using a selector list, and applies/removes a .hovered class; exposes bind(), updateFromPoint(), and clear().
- ui/views/CommonwealthOnline/browser/app.js & index.html: include and bind the new hover component during UI initialization.
- ui/views/CommonwealthOnline/browser/styles.css: add .hovered variants and transitions for nav items, buttons, rows, and filter controls to match hover visuals.
- steam_interfaces.txt: add a list of Steam interface version strings (new file).

Purpose: ensure custom buttons/rows that don't receive native :hover updates from the renderer get visible hover feedback by syncing the native cursor into the web UI and toggling a .hovered class.

ui/views/CommonwealthOnline/browser/index.html

@@ -87,6 +87,7 @@
   <script src="./components/server-details.js"></script>
   <script src="./components/controller-prompts.js"></script>
   <script src="./components/direct-connect.js"></script>
+  <script src="./components/hover.js"></script>
   <script src="./app.js"></script>
 </body>
 </html>