Add AI usage logs for Gemini and Whisper

- Migration + AiUsageLog model with tokens, duration, time, cost fields
- GeminiIntentService and GeminiVisionService log every API call
  with input/output token counts from usageMetadata and response time
- TelegramBotService logs Whisper calls with audio duration (from Telegram)
  and calculates cost at $1/second
- Whisper voice duration now passed from TelegramWebhookController
- Free text in Telegram now tries Gemini intent detection before showing menu
- /chat/ia-logs: Livewire component with summary cards + filterable table
- Whisper connection test button in config panel
- "Logs IA" link added to Chat/Bot nav section

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

app/Models/AiUsageLog.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Model;
+
+class AiUsageLog extends Model
+{
+    protected $table = 'ai_usage_logs';
+
+    protected $fillable = [
+        'servicio', 'canal', 'usuario_id',
+        'input_tokens', 'output_tokens', 'audio_segundos',
+        'tiempo_ms', 'costo', 'resultado', 'detalle',
+    ];
+
+    protected $casts = ['detalle' => 'array'];
+
+    public static function registrar(array $data): void
+    {
+        try {
+            static::create($data);
+        } catch (\Throwable) {
+            // No interrumpir el flujo principal si el log falla
+        }
+    }
+}