Remove OKX configuration file and enhance data collector with timeframes support

- Deleted the `okx_config.json` file as part of the configuration refactor.
- Updated `BaseDataCollector` to include an optional `timeframes` parameter for more flexible data collection.
- Modified `DataCollectionService` and `OKXCollector` to pass and utilize the new `timeframes` parameter.
- Enhanced `ExchangeCollectorConfig` to validate timeframes, ensuring they are provided and correctly formatted.
- Updated documentation to reflect the new configurable timeframes feature, improving clarity for users.

These changes streamline the configuration process and improve the flexibility of data collection, aligning with project standards for maintainability and usability.

config/okx_config.json

@@ -1,69 +0,0 @@
-{
-  "exchange": "okx",
-  "connection": {
-    "public_ws_url": "wss://ws.okx.com:8443/ws/v5/public",
-    "private_ws_url": "wss://ws.okx.com:8443/ws/v5/private",
-    "ping_interval": 25.0,
-    "pong_timeout": 10.0,
-    "max_reconnect_attempts": 5,
-    "reconnect_delay": 5.0
-  },
-  "data_collection": {
-    "store_raw_data": true,
-    "health_check_interval": 120.0,
-    "auto_restart": true,
-    "buffer_size": 1000
-  },
-  "factory": {
-    "use_factory_pattern": true,
-    "default_data_types": ["trade", "orderbook"],
-    "default_timeframes": ["1s", "5s", "1m", "5m", "15m", "1h"],
-    "batch_create": true
-  },
-  "trading_pairs": [
-    {
-      "symbol": "BTC-USDT",
-      "enabled": true,
-      "data_types": ["trade", "orderbook"],
-      "timeframes": ["1s", "5s", "1m", "5m", "15m", "1h"],
-      "channels": {
-        "trades": "trades",
-        "orderbook": "books5",
-        "ticker": "tickers"
-      }
-    },
-    {
-      "symbol": "ETH-USDT",
-      "enabled": true,
-      "data_types": ["trade", "orderbook"],
-      "timeframes": ["1s", "5s", "1m", "5m", "15m", "1h"],
-      "channels": {
-        "trades": "trades",
-        "orderbook": "books5",
-        "ticker": "tickers"
-      }
-    }
-  ],
-  "logging": {
-    "component_name_template": "okx_collector_{symbol}",
-    "log_level": "INFO",
-    "verbose": false
-  },
-  "database": {
-    "store_processed_data": true,
-    "store_raw_data": false,
-    "force_update_candles": false,
-    "batch_size": 100,
-    "flush_interval": 5.0
-  },
-  "rate_limiting": {
-    "max_subscriptions_per_connection": 100,
-    "max_messages_per_second": 1000
-  },
-  "monitoring": {
-    "enable_health_checks": true,
-    "health_check_interval": 30.0,
-    "alert_on_connection_loss": true,
-    "max_consecutive_errors": 5
-  }
-}