Announce New Chat workspace transiently

static/style.css

@@ -1519,6 +1519,7 @@
     }
   }
   html{background:var(--sidebar);}
+  .sr-only{position:absolute!important;width:1px!important;height:1px!important;padding:0!important;margin:-1px!important;overflow:hidden!important;clip:rect(0 0 0 0)!important;clip-path:inset(50%)!important;white-space:nowrap!important;border:0!important;}
   body{background:var(--bg);color:var(--text);height:100vh;height:100dvh;overflow:hidden;display:flex;flex-direction:column;}
   .layout{display:flex;width:100%;flex:1 1 auto;min-height:0;}
   .app-titlebar{display:flex;align-items:center;justify-content:center;height:38px;flex-shrink:0;background:var(--sidebar);border-bottom:1px solid var(--border);padding:0 12px;padding-top:var(--app-titlebar-safe-top);padding-left:max(12px,env(safe-area-inset-left,0));padding-right:max(12px,env(safe-area-inset-right,0));box-sizing:content-box;font-size:12px;color:var(--muted);user-select:none;-webkit-app-region:drag;position:relative;z-index:20;}