fix: SSE keepalive via plugin-kit 0.1.4 (v0.3.1)

Live-verified against a running host: status frames (including a syncing
transition) now stream through the plugin UI server. The previous keepalive
outlived Bun's default idle timeout, so an idle feed was closed before its
first ping.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

ui/package.json

@@ -15,7 +15,7 @@
 	"dependencies": {
 		"@effect/atom-react": "4.0.0-beta.99",
 		"@fontsource-variable/geist": "^5.2.9",
-		"@punktfunk/plugin-kit": "^0.1.3",
+		"@punktfunk/plugin-kit": "^0.1.4",
 		"@unom/app-ui": "^0.2.0",
 		"@unom/style": "^0.4.4",
 		"@unom/ui": "^0.9.1",