Attribute Macro shape_provider 

#[shape_provider]

Attribute macro for Shape data providers.

Extracts metadata from doc comments and generates a PROVIDER_METADATA_<NAME> constant.

Usage

/// Market data provider with DuckDB backend
///
/// # Parameters
/// * `symbol: String` - Stock symbol (required)
/// * `timeframe: String` - Time period (required)
///
/// # Example
/// ```shape
/// data('market_data', {symbol: 'ES', timeframe: '1h'})
/// ```
#[shape_provider(category = "Market Data")]
pub fn market_data_provider(args: Vec<Value>, ctx: &mut ExecutionContext) -> Result<Value> {
    // implementation
}