Add OKX data collector implementation and modular exchange architecture

- Introduced the `OKXCollector` and `OKXWebSocketClient` classes for real-time market data collection from the OKX exchange.
- Implemented a factory pattern for creating exchange-specific collectors, enhancing modularity and scalability.
- Added configuration support for the OKX collector in `config/okx_config.json`.
- Updated documentation to reflect the new modular architecture and provide guidance on using the OKX collector.
- Created unit tests for the OKX collector and exchange factory to ensure functionality and reliability.
- Enhanced logging and error handling throughout the new implementation for improved monitoring and debugging.

config/okx_config.json

@@ -0,0 +1,65 @@
+{
+  "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": 30.0,
+    "auto_restart": true,
+    "buffer_size": 1000
+  },
+  "factory": {
+    "use_factory_pattern": true,
+    "default_data_types": ["trade", "orderbook"],
+    "batch_create": true
+  },
+  "trading_pairs": [
+    {
+      "symbol": "BTC-USDT",
+      "enabled": true,
+      "data_types": ["trade", "orderbook"],
+      "channels": {
+        "trades": "trades",
+        "orderbook": "books5",
+        "ticker": "tickers"
+      }
+    },
+    {
+      "symbol": "ETH-USDT",
+      "enabled": true,
+      "data_types": ["trade", "orderbook"],
+      "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": true,
+    "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
+  }
+}