ui: Add MCP Servers Opt-In for first time visitors (#25239)

* feat: ui: Add predefined recommended MCP servers to settings

* feat: ui: Add MCP server recommendation dialog with custom server support

* feat: Auto-focus input fields on mount and dynamic addition

* feat: Add header validation to MCP server add and edit forms

* feat: Persist recommended MCP server opt-in selections

* test: Cover MCP configuration with tests

* chore: Format & cleanup

* feat: Centralize MCP server overrides to settings config and improve recommendation UI

* fix: Capture index before mutation to prevent focus drift

* refactor: Extract MCP_CARD_VISIBLE_TOOL_LIMIT to shared constants

* refactor: Support arbitrary authorization header schemes

* refactor: Consolidate MCP recommendations dismissal into existing storage key

* fix: Use case-insensitive comparison for MCP server ID prefix check

* refactor: Centralize MCP server visibility logic and extract recommendations hook

* refactor: Cleanup

tools/ui/src/lib/components/app/settings/SettingsMcpServers.svelte

@@ -21,7 +21,7 @@
 
 	let { class: className }: Props = $props();
 
-	let servers = $derived(mcpStore.getServersSorted());
+	let servers = $derived(mcpStore.visibleMcpServers);
 
 	let initialLoadComplete = $state(false);
 	let isAddingServer = $state(false);