Interface FeeEstimate

interface FeeEstimate {
    confidence: "low" | "medium" | "high";
    confirmationTarget: number;
    estimatedTime: string;
    feeRate: number;
    priority: "low" | "medium" | "high" | "urgent" | "economy";
    source: "electrumx" | "fallback" | "cached";
    timestamp: number;
}