Clarify cost display as API-rate estimate

Sources/CodexBar/CostHistoryChartMenuView.swift

@@ -148,9 +148,11 @@ struct CostHistoryChartMenuView: View {
             }
 
             if let total = self.totalCostUSD {
-                Text("Total (30d): \(UsageFormatter.usdString(total))")
+                Text("Est. total (30d): \(UsageFormatter.usdString(total))")
                     .font(.caption)
                     .foregroundStyle(.secondary)
+                    .lineLimit(1)
+                    .truncationMode(.head)
             }
         }
         .padding(.horizontal, 16)

Sources/CodexBar/MenuCardView.swift

@@ -181,7 +181,7 @@ struct UsageMenuCardView: View {
                     }
                     if let tokenUsage = self.model.tokenUsage {
                         VStack(alignment: .leading, spacing: 6) {
-                            Text("Cost")
+                            Text("cost_header_estimated")
                                 .font(.body)
                                 .fontWeight(.medium)
                             Text(tokenUsage.sessionLine)
@@ -598,7 +598,7 @@ struct UsageMenuCardCostSectionView: View {
                 VStack(alignment: .leading, spacing: 10) {
                     if let tokenUsage = self.model.tokenUsage {
                         VStack(alignment: .leading, spacing: 6) {
-                            Text("Cost")
+                            Text("cost_header_estimated")
                                 .font(.body)
                                 .fontWeight(.medium)
                             Text(tokenUsage.sessionLine)
@@ -1556,7 +1556,7 @@ extension UsageMenuCardView.Model {
         return TokenUsageSection(
             sessionLine: sessionLine,
             monthLine: monthLine,
-            hintLine: nil,
+            hintLine: String(localized: "cost_estimate_hint"),
             errorLine: err,
             errorCopyText: (error?.isEmpty ?? true) ? nil : error)
     }

Sources/CodexBar/Resources/en.lproj/Localizable.strings

@@ -622,3 +622,7 @@
 "refresh_5min" = "5 min";
 "refresh_15min" = "15 min";
 "refresh_30min" = "30 min";
+
+/* Cost estimation */
+"cost_header_estimated" = "Cost (estimated)";
+"cost_estimate_hint" = "Estimated from local logs · may differ from your bill";

Sources/CodexBar/Resources/pt-BR.lproj/Localizable.strings

@@ -602,3 +602,7 @@
 "refresh_5min" = "5 min";
 "refresh_15min" = "15 min";
 "refresh_30min" = "30 min";
+
+/* Cost estimation */
+"cost_header_estimated" = "Custo (estimado)";
+"cost_estimate_hint" = "Estimado a partir de logs locais · pode diferir da sua fatura";

Sources/CodexBar/Resources/zh-Hans.lproj/Localizable.strings

@@ -632,3 +632,7 @@
 
 /* Additional keys */
 "not_found" = "未找到";
+
+/* Cost estimation */
+"cost_header_estimated" = "费用（估算）";
+"cost_estimate_hint" = "根据本地日志估算 · 可能与账单不同";

Sources/CodexBarCLI/CLICostCommand.swift

@@ -79,7 +79,7 @@ extension CodexBarCLI {
         useColor: Bool) -> String
     {
         let name = ProviderDescriptorRegistry.descriptor(for: provider).metadata.displayName
-        let header = Self.costHeaderLine("\(name) Cost (local)", useColor: useColor)
+        let header = Self.costHeaderLine("\(name) Cost (API-rate estimate)", useColor: useColor)
 
         let todayCost = snapshot.sessionCostUSD.map { UsageFormatter.usdString($0) } ?? "—"
         let todayTokens = snapshot.sessionTokens.map { UsageFormatter.tokenCountString($0) }
@@ -89,7 +89,7 @@ extension CodexBarCLI {
         let monthTokens = snapshot.last30DaysTokens.map { UsageFormatter.tokenCountString($0) }
         let monthLine = monthTokens.map { "Last 30 days: \(monthCost) · \($0) tokens" } ?? "Last 30 days: \(monthCost)"
 
-        return [header, todayLine, monthLine].joined(separator: "\n")
+        return [header, todayLine, monthLine, UsageFormatter.costEstimateHint].joined(separator: "\n")
     }
 
     private static func costHeaderLine(_ header: String, useColor: Bool) -> String {

Sources/CodexBarCore/UsageFormatter.swift

@@ -109,6 +109,8 @@ public enum UsageFormatter {
         value.formatted(.currency(code: "USD").locale(Locale(identifier: "en_US")))
     }
 
+    public static let costEstimateHint = "Estimated from local logs · may differ from your bill"
+
     /// Formats a currency value with the specified currency code.
     /// Uses FormatStyle with explicit en_US locale to ensure consistent formatting
     /// regardless of the user's system locale (e.g., pt-BR users see $54.72 not US$ 54,72).

Tests/CodexBarTests/CLICostTests.swift

@@ -30,9 +30,10 @@ struct CLICostTests {
             .replacingOccurrences(of: "\u{00A0}", with: " ")
             .replacingOccurrences(of: "$ ", with: "$")
 
-        #expect(output.contains("Claude Cost (local)"))
+        #expect(output.contains("Claude Cost (API-rate estimate)"))
         #expect(output.contains("Today: $1.25 · 1.2K tokens"))
         #expect(output.contains("Last 30 days: $9.99 · 9K tokens"))
+        #expect(output.contains(UsageFormatter.costEstimateHint))
     }
 
     @Test
@@ -138,4 +139,11 @@ struct CLICostTests {
         #expect(json.contains("\"cost\":0"))
         #expect(json.contains("\"totalTokens\":140"))
     }
+
+    @Test
+    func `cost estimate hint is stable string`() {
+        let hint = UsageFormatter.costEstimateHint
+        #expect(!hint.isEmpty)
+        #expect(hint.contains("Estimated"))
+    }
 }