Add mcpServersLoaded store to track server load state

Introduces a new writable store, mcpServersLoaded, to indicate when MCP servers have finished loading. Updates ChatWindow.svelte to only show router examples after servers are loaded, improving UI consistency and preventing premature rendering.

src/lib/components/chat/ChatWindow.svelte

@@ -27,7 +27,7 @@
 	import { routerExamples } from "$lib/constants/routerExamples";
 	import { mcpExamples } from "$lib/constants/mcpExamples";
 	import type { RouterFollowUp, RouterExample } from "$lib/constants/routerExamples";
-	import { allBaseServersEnabled } from "$lib/stores/mcpServers";
+	import { allBaseServersEnabled, mcpServersLoaded } from "$lib/stores/mcpServers";
 	import { shareModal } from "$lib/stores/shareModal";
 	import CarbonTools from "~icons/carbon/tools";
 
@@ -438,7 +438,7 @@
 			dark:from-gray-900 dark:via-gray-900/100
 			dark:to-gray-900/0 max-sm:py-0 sm:px-5 md:pb-4 xl:max-w-4xl [&>*]:pointer-events-auto"
 	>
-		{#if !draft.length && !messages.length && !sources.length && !loading && currentModel.isRouter && activeExamples.length && !hideRouterExamples && !lastIsError}
+		{#if !draft.length && !messages.length && !sources.length && !loading && currentModel.isRouter && activeExamples.length && !hideRouterExamples && !lastIsError && $mcpServersLoaded}
 			<div
 				class="no-scrollbar mb-3 flex w-full select-none justify-start gap-2 overflow-x-auto whitespace-nowrap text-gray-400 dark:text-gray-500"
 			>

src/lib/stores/mcpServers.ts

@@ -104,6 +104,9 @@ function saveDisabledBaseIds(ids: Set<string>) {
 // Store for all servers (base + custom)
 export const allMcpServers = writable<MCPServer[]>([]);
 
+// Track if initial server load has completed
+export const mcpServersLoaded = writable<boolean>(false);
+
 // Store for selected server IDs
 export const selectedServerIds = writable<Set<string>>(loadSelectedIds());
 
@@ -176,10 +179,12 @@ export async function refreshMcpServers() {
 
 			return newSelection;
 		});
+		mcpServersLoaded.set(true);
 	} catch (error) {
 		console.error("Failed to refresh MCP servers:", error);
 		// On error, just use custom servers
 		allMcpServers.set(loadCustomServers());
+		mcpServersLoaded.set(true);
 	}
 }