feat: add Reset Stats button to admin LLM tracking panel

Allows resetting the LLM stats aggregation window without deleting
historical data. Stores a reset timestamp in metadata and filters
the aggregation query to only include calls after that point.

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

server/src/llm/llmStatsService.ts

@@ -16,6 +16,7 @@ export interface LlmStatsService {
   getStats(): LlmStatsData;
   isTrackingEnabled(): boolean;
   setTrackingEnabled(enabled: boolean): void;
+  resetStats(): void;
 }
 
 export function createLlmStatsService(): LlmStatsService {
@@ -52,6 +53,12 @@ export function createLlmStatsService(): LlmStatsService {
       const enabled = loadTrackingEnabled();
       try {
         const db = getDatabase();
+        const resetRow = db.prepare("SELECT value FROM metadata WHERE key = 'llm_stats_reset_after'").get() as { value: string } | undefined;
+        const resetAfter = resetRow?.value ?? null;
+
+        const whereClause = resetAfter ? 'WHERE timestamp > ?' : '';
+        const params = resetAfter ? [resetAfter] : [];
+
         const rows = db.prepare(`
           SELECT
             template_name,
@@ -63,9 +70,10 @@ export function createLlmStatsService(): LlmStatsService {
             SUM(CASE WHEN retries > 0 THEN 1 ELSE 0 END) as retry_count,
             SUM(failed) as fail_count
           FROM llm_call_log
+          ${whereClause}
           GROUP BY template_name
           ORDER BY count DESC
-        `).all() as Array<{
+        `).all(...params) as Array<{
           template_name: string;
           count: number;
           total_cost: number;
@@ -114,5 +122,14 @@ export function createLlmStatsService(): LlmStatsService {
         // ignore
       }
     },
+
+    resetStats(): void {
+      try {
+        const db = getDatabase();
+        db.prepare("INSERT OR REPLACE INTO metadata (key, value) VALUES ('llm_stats_reset_after', ?)").run(new Date().toISOString());
+      } catch {
+        // ignore
+      }
+    },
   };
 }

server/src/network/SocketServer.ts

@@ -204,6 +204,14 @@ export class SocketServer {
         socket.emit('admin-llm-stats-result', stats);
       });
 
+      socket.on('admin-reset-llm-stats', () => {
+        if (!this.authenticatedSockets.has(socket.id)) return;
+        this.gameLoop.llmStatsService.resetStats();
+        const stats = this.gameLoop.llmStatsService.getStats();
+        socket.emit('admin-llm-stats-result', stats);
+        this.gameLoop.logService.log('info', 'Game', 'Admin reset LLM stats');
+      });
+
       socket.on('admin-toggle-llm-tracking', (data: { enabled: boolean }) => {
         if (!this.authenticatedSockets.has(socket.id)) return;
         this.gameLoop.llmStatsService.setTrackingEnabled(data.enabled);