feat: add LoL Stats plugin — op.gg-powered player lookup

New plugin for League of Legends stats tracking, similar to op.gg:
- Search summoners by Riot ID (Name#Tag) + region
- Profile overview: rank, tier, LP, win rate, ladder position
- Top champions with KDA and win rates
- Match history with KDA, CS, items, game duration
- Expandable match details showing all 10 players
- Recent searches persisted across restarts

Uses op.gg MCP server (no API key needed, no 24h expiration).
Backend: server/src/plugins/lolstats/ (3 files)
Frontend: web/src/plugins/lolstats/ (2 files)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

web/src/App.tsx

@@ -1,6 +1,7 @@
 import { useState, useEffect, useRef } from 'react';
 import RadioTab from './plugins/radio/RadioTab';
 import SoundboardTab from './plugins/soundboard/SoundboardTab';
+import LolstatsTab from './plugins/lolstats/LolstatsTab';
 
 interface PluginInfo {
   name: string;
@@ -12,6 +13,7 @@ interface PluginInfo {
 const tabComponents: Record<string, React.FC<{ data: any }>> = {
   radio: RadioTab,
   soundboard: SoundboardTab,
+  lolstats: LolstatsTab,
 };
 
 export function registerTab(pluginName: string, component: React.FC<{ data: any }>) {
@@ -79,6 +81,7 @@ export default function App() {
   const tabIcons: Record<string, string> = {
     radio: '\u{1F30D}',
     soundboard: '\u{1F3B5}',
+    lolstats: '\u{2694}\uFE0F',
     stats: '\u{1F4CA}',
     events: '\u{1F4C5}',
     games: '\u{1F3B2}',