feat(billing): add usage analytics charts and summary totals

Add daily usage trend charts with multi-metric toggles, overview vs user
analysis views, date-range filtering, and usage summary API for interval
and all-time totals.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/types.ts

@@ -247,6 +247,37 @@ export type UsageRecord = {
   createdAt: number;
 };
 
+export type UsageStatsBucket = {
+  day: string;
+  count: number;
+  inputTokens: number;
+  outputTokens: number;
+  costCents: number;
+};
+
+export type UsageTotals = {
+  count: number;
+  inputTokens: number;
+  outputTokens: number;
+  costCents: number;
+};
+
+export type UsageRangeTotals = UsageTotals & {
+  startAt: number;
+  endAt: number;
+};
+
+export type UsageSummaryResult = {
+  range: UsageRangeTotals | null;
+  allTime: UsageTotals;
+};
+
+export type UsageStatsResult = {
+  buckets: UsageStatsBucket[];
+  startAt: number;
+  endAt: number;
+};
+
 export type LedgerEntry = {
   id: number;
   userId: string;
@@ -343,6 +374,14 @@ export type MemoryV2AdminConfigResponse = {
   updatedBy: string | null;
 };
 
+export type MemoryV2ConfigRuntimeState = {
+  source: string;
+  updatedAt: number | null;
+  updatedBy: string | null;
+  fingerprint?: string;
+  overrides: Record<string, string>;
+};
+
 export type MemoryV2RuntimeStatusResponse = {
   ok: boolean;
   checkedAt?: number;