Restyle server browser UI; hide overlay on join

Restyles the server browser to match main-menu/settings (Futura PT Demibold, amber/green palette, yellow selection bars, shared panel chrome), removes SVG border strips, and tweaks modal width/layout. Adds JS + C++ coordination so the custom main-menu overlay hides when a server join begins (C++ invokes onSessionLoading and calls HideMainMenu; CompleteJoinFailure restores the menu/browser). Controller glyph tint now derives from --co-amber. Updates changelog and dev-log; includes compiled Vault109 script update.

ui/views/CommonwealthOnline/main-menu/script.js

@@ -472,6 +472,39 @@
     exitBrowserMode(true);
   };
 
+  window.onMainMenuShown = function () {
+    if (mainScreen) {
+      mainScreen.classList.remove("is-session-loading");
+    }
+  };
+
+  window.onSessionLoading = function () {
+    if (viewMode === "browser") {
+      cancelBrowserPanelHide();
+      browserController.hide();
+      browserPanel.classList.remove("is-open");
+      browserPanel.hidden = true;
+    } else if (viewMode === "settings") {
+      cancelSettingsPanelHide();
+      settingsController.hide();
+      settingsPanel.classList.remove("is-open");
+      settingsPanel.hidden = true;
+    }
+
+    viewMode = "menu";
+    if (mainScreen) {
+      mainScreen.classList.remove("is-browser-mode", "is-settings-mode");
+      mainScreen.classList.add("is-session-loading");
+    }
+    if (mainPromptBar) {
+      mainPromptBar.hidden = true;
+    }
+    if (settingsPromptBar) {
+      settingsPromptBar.hidden = true;
+    }
+    setSelected(-1);
+  };
+
   function enterSettingsMode() {
     if (viewMode === "browser") {
       cancelBrowserPanelHide();

ui/views/CommonwealthOnline/main-menu/styles.css

@@ -62,6 +62,12 @@ body {
   overflow: hidden;
 }
 
+.main-screen.is-session-loading {
+  opacity: 0;
+  visibility: hidden;
+  pointer-events: none;
+}
+
 /* ── Title-screen scenic background ──────────────────────────── */
 
 .scene-layer {