feat(core): display quota renewal date

Render subscription renewal dates and countdowns in quota output, normalize numeric period-end timestamps, and cover UTC and edge-case behavior.

src/quota-format.ts

@@ -49,10 +49,42 @@ function creditsDetail(credits: CommandCodeCredits | null): string | undefined {
   return `Sources: ${parts.join(" / ")}`
 }
 
-function subscriptionLine(subscription: CommandCodeSubscription): string {
+function parsePeriodEnd(value: string): Date | null {
+  const trimmed = value.trim()
+  const timestamp = /^\d+$/.test(trimmed) ? Number(trimmed) : Date.parse(trimmed)
+  if (!Number.isFinite(timestamp) || timestamp < 0) return null
+  const milliseconds = timestamp >= 1e12 ? timestamp : timestamp * 1000
+  const date = new Date(milliseconds)
+  return Number.isNaN(date.getTime()) ? null : date
+}
+
+function subscriptionLine(
+  subscription: CommandCodeSubscription,
+  now: () => number = Date.now,
+): string {
   const plan = (subscription.planId ?? "Unknown").replace(/[_-]+/g, " ").trim()
   const status = subscription.status ? ` (${subscription.status})` : ""
-  return `Plan: ${plan}${status}`
+  let renewal = ""
+  if (subscription.currentPeriodEnd) {
+    const end = parsePeriodEnd(subscription.currentPeriodEnd)
+    if (end) {
+      const diffMs = end.getTime() - now()
+      const days = Math.ceil(diffMs / 86_400_000)
+      const dateStr = end.toLocaleDateString("en-US", {
+        month: "short",
+        day: "numeric",
+        timeZone: "UTC",
+      })
+      if (days > 0) {
+        renewal = ` · renews ${dateStr} (${days}d)`
+      } else if (days === 0) {
+        renewal = ` · renews ${dateStr} (today)`
+      } else {
+        renewal = ` · renewed ${dateStr}`
+      }
+    }
+  }
+  return `Plan: ${plan}${status}${renewal}`
 }
 
 function formatTokens(tokens: number): string {
@@ -77,7 +109,7 @@ export function formatQuota(quota: CommandCodeQuota, now: () => number = Date.no
 
   const detail = creditsDetail(quota.credits)
   if (detail) lines.push(detail)
-  if (quota.subscription) lines.push(subscriptionLine(quota.subscription))
+  if (quota.subscription) lines.push(subscriptionLine(quota.subscription, now))
 
   if (quota.summary) {
     lines.push("")

src/quota.ts

@@ -43,6 +43,13 @@ function stringValue(value: unknown): string | undefined {
   return typeof value === "string" && value.length > 0 ? value : undefined
 }
 
+function timestampValue(value: unknown): string | undefined {
+  const text = stringValue(value)
+  if (text) return text
+  const number = numberValue(value)
+  return number === undefined ? undefined : String(number)
+}
+
 function errorMessage(error: unknown): string {
   return error instanceof Error ? error.message : String(error)
 }
@@ -100,8 +107,8 @@ function parseSubscription(value: unknown): CommandCodeSubscription | null {
   const data = value.data
   const planId = stringValue(data.planId)
   const status = stringValue(data.status)
-  const currentPeriodStart = stringValue(data.currentPeriodStart)
-  const currentPeriodEnd = stringValue(data.currentPeriodEnd)
+  const currentPeriodStart = timestampValue(data.currentPeriodStart)
+  const currentPeriodEnd = timestampValue(data.currentPeriodEnd)
   if (!planId && !status && !currentPeriodStart && !currentPeriodEnd) return null
   return {
     planId: planId ?? null,