Usage: add cost summaries to /usage + mac menu

apps/macos/Sources/Clawdbot/UsageCostData.swift

@@ -0,0 +1,60 @@
+import Foundation
+
+struct GatewayCostUsageTotals: Codable {
+    let input: Int
+    let output: Int
+    let cacheRead: Int
+    let cacheWrite: Int
+    let totalTokens: Int
+    let totalCost: Double
+    let missingCostEntries: Int
+}
+
+struct GatewayCostUsageDay: Codable {
+    let date: String
+    let input: Int
+    let output: Int
+    let cacheRead: Int
+    let cacheWrite: Int
+    let totalTokens: Int
+    let totalCost: Double
+    let missingCostEntries: Int
+}
+
+struct GatewayCostUsageSummary: Codable {
+    let updatedAt: Double
+    let days: Int
+    let daily: [GatewayCostUsageDay]
+    let totals: GatewayCostUsageTotals
+}
+
+enum CostUsageFormatting {
+    static func formatUsd(_ value: Double?) -> String? {
+        guard let value, value.isFinite else { return nil }
+        if value >= 1 { return String(format: "$%.2f", value) }
+        if value >= 0.01 { return String(format: "$%.2f", value) }
+        return String(format: "$%.4f", value)
+    }
+
+    static func formatTokenCount(_ value: Int?) -> String? {
+        guard let value else { return nil }
+        let safe = max(0, value)
+        if safe >= 1_000_000 { return String(format: "%.1fm", Double(safe) / 1_000_000.0) }
+        if safe >= 1000 { return safe >= 10000
+            ? String(format: "%.0fk", Double(safe) / 1000.0)
+            : String(format: "%.1fk", Double(safe) / 1000.0)
+        }
+        return String(safe)
+    }
+}
+
+@MainActor
+enum CostUsageLoader {
+    static func loadSummary() async throws -> GatewayCostUsageSummary {
+        let data = try await ControlChannel.shared.request(
+            method: "usage.cost",
+            params: nil,
+            timeoutMs: 7000)
+        return try JSONDecoder().decode(GatewayCostUsageSummary.self, from: data)
+    }
+}