perf(electrobun): fix CEF high CPU — disable GPU flags + remove CSS animations

- electrobun.config.ts: add --disable-gpu --disable-gpu-compositing to CEF
  flags (GLXBadWindow X11 errors cause continuous recovery loop)
- StatusBar.svelte: replace @keyframes pulse with CSS transition + JS toggle
- app.css: remove @keyframes pulse-dot (continuous compositor repaint)

CSS animations on small elements cause 10-30% CPU in both CEF and WebKitGTK.
JS class toggle with transition: opacity 0.3s uses near-zero CPU.

ui-electrobun/electrobun.config.ts

@@ -7,7 +7,15 @@ const useCEF = process.env.AGOR_CEF === "1";
 
 // When CEF is active, enable remote debugging for CDP-based E2E automation.
 const cefFlags: Record<string, string | boolean> | undefined = useCEF
-	? { "remote-debugging-port": "9222", "remote-allow-origins": "*" }
+	? {
+			"remote-debugging-port": "9222",
+			"remote-allow-origins": "*",
+			// Reduce CPU: disable GPU acceleration (GLXBadWindow errors on Linux
+			// cause continuous error recovery loop in software fallback mode)
+			"disable-gpu": true,
+			"disable-gpu-compositing": true,
+			"disable-software-rasterizer": false,
+		}
 	: undefined;
 
 export default {