export interface EnvConfig {
    log_level?: string;
    model_override?: string;
    [key: string]: any;
}
/**
 * Load environment configuration.
 * Loads config/default.yaml, then merges config/<env>.yaml on top.
 * Env is determined by --env flag or GITAGENT_ENV environment variable.
 */
export declare function loadEnvConfig(agentDir: string, env?: string): Promise<EnvConfig>;