chore: remove configuration files and enhance blockchain explorer with advanced search, analytics, and export features

- Delete .aitbc.yaml.example CLI configuration template
- Delete .lycheeignore link checker exclusion rules
- Delete .nvmrc Node.js version specification
- Add advanced search panel with filters for address, amount range, transaction type, time range, and validator
- Add analytics dashboard with transaction volume, active addresses, and block time metrics
- Add Chart.js integration

cli/aitbc_cli/core/config.py

@@ -0,0 +1,101 @@
+"""
+Multi-chain configuration management for AITBC CLI
+"""
+
+from pathlib import Path
+from typing import Dict, Any, Optional
+import yaml
+from pydantic import BaseModel, Field
+
+class NodeConfig(BaseModel):
+    """Configuration for a specific node"""
+    id: str = Field(..., description="Node identifier")
+    endpoint: str = Field(..., description="Node endpoint URL")
+    timeout: int = Field(default=30, description="Request timeout in seconds")
+    retry_count: int = Field(default=3, description="Number of retry attempts")
+    max_connections: int = Field(default=10, description="Maximum concurrent connections")
+
+class ChainConfig(BaseModel):
+    """Default chain configuration"""
+    default_gas_limit: int = Field(default=10000000, description="Default gas limit")
+    default_gas_price: int = Field(default=20000000000, description="Default gas price in wei")
+    max_block_size: int = Field(default=1048576, description="Maximum block size in bytes")
+    backup_path: Path = Field(default=Path("./backups"), description="Backup directory path")
+    max_concurrent_chains: int = Field(default=100, description="Maximum concurrent chains per node")
+
+class MultiChainConfig(BaseModel):
+    """Multi-chain configuration"""
+    nodes: Dict[str, NodeConfig] = Field(default_factory=dict, description="Node configurations")
+    chains: ChainConfig = Field(default_factory=ChainConfig, description="Chain configuration")
+    logging_level: str = Field(default="INFO", description="Logging level")
+    enable_caching: bool = Field(default=True, description="Enable response caching")
+    cache_ttl: int = Field(default=300, description="Cache TTL in seconds")
+
+def load_multichain_config(config_path: Optional[str] = None) -> MultiChainConfig:
+    """Load multi-chain configuration from file"""
+    if config_path is None:
+        config_path = Path.home() / ".aitbc" / "multichain_config.yaml"
+    
+    config_file = Path(config_path)
+    
+    if not config_file.exists():
+        # Create default configuration
+        default_config = MultiChainConfig()
+        save_multichain_config(default_config, config_path)
+        return default_config
+    
+    try:
+        with open(config_file, 'r') as f:
+            config_data = yaml.safe_load(f)
+        
+        return MultiChainConfig(**config_data)
+    except Exception as e:
+        raise ValueError(f"Failed to load configuration from {config_path}: {e}")
+
+def save_multichain_config(config: MultiChainConfig, config_path: Optional[str] = None) -> None:
+    """Save multi-chain configuration to file"""
+    if config_path is None:
+        config_path = Path.home() / ".aitbc" / "multichain_config.yaml"
+    
+    config_file = Path(config_path)
+    config_file.parent.mkdir(parents=True, exist_ok=True)
+    
+    try:
+        # Convert Path objects to strings for YAML serialization
+        config_dict = config.dict()
+        if 'chains' in config_dict and 'backup_path' in config_dict['chains']:
+            config_dict['chains']['backup_path'] = str(config_dict['chains']['backup_path'])
+        
+        with open(config_file, 'w') as f:
+            yaml.dump(config_dict, f, default_flow_style=False, indent=2)
+    except Exception as e:
+        raise ValueError(f"Failed to save configuration to {config_path}: {e}")
+
+def get_default_node_config() -> NodeConfig:
+    """Get default node configuration for local development"""
+    return NodeConfig(
+        id="default-node",
+        endpoint="http://localhost:8545",
+        timeout=30,
+        retry_count=3,
+        max_connections=10
+    )
+
+def add_node_config(config: MultiChainConfig, node_config: NodeConfig) -> MultiChainConfig:
+    """Add a node configuration"""
+    config.nodes[node_config.id] = node_config
+    return config
+
+def remove_node_config(config: MultiChainConfig, node_id: str) -> MultiChainConfig:
+    """Remove a node configuration"""
+    if node_id in config.nodes:
+        del config.nodes[node_id]
+    return config
+
+def get_node_config(config: MultiChainConfig, node_id: str) -> Optional[NodeConfig]:
+    """Get a specific node configuration"""
+    return config.nodes.get(node_id)
+
+def list_node_configs(config: MultiChainConfig) -> Dict[str, NodeConfig]:
+    """List all node configurations"""
+    return config.nodes.copy()