Expose gateway billing flows from the synced server baseline

The preserved local work adds PopiNewAPI billing checkout, gateway account binding, and matching web console/pricing surfaces on top of the current test-server baseline. During the merge, the start-end video helpers from the deployed baseline were kept alongside the actionGenerate prompt handling from the WIP.

Constraint: Current usable baseline is 7054436, already deployed on the test server.

Rejected: Commit the WIP before syncing the baseline | would have hidden conflicts with the deployed start-end-frame changes.

Confidence: medium

Scope-risk: broad

Directive: Do not deploy this commit to the test server without rechecking gateway credentials and billing checkout behavior in that environment.

Tested: go test ./...

Tested: make build

Tested: cd web && npm run build

web/lib/popiart-api.ts

@@ -29,6 +29,9 @@ export type AuthSessionView = {
   user: PopiartUser;
   session_key?: string;
   upstream_key_masked?: string;
+  gateway_user_id?: number;
+  gateway_access_token_masked?: string;
+  gateway_bound: boolean;
 };
 
 export type Skill = {
@@ -84,6 +87,149 @@ export type BudgetUsage = {
   };
 };
 
+export type Project = {
+  id: string;
+  name: string;
+};
+
+export type ProjectListResponse = {
+  items: Project[];
+  total: number;
+  limit: number;
+  offset: number;
+};
+
+export type BillingPlan = {
+  id: string;
+  product_type: string;
+  badge: string;
+  name: string;
+  price: string;
+  cadence: string;
+  summary: string;
+  features: string[];
+  cta: string;
+  highlight?: boolean;
+};
+
+export type BillingCatalog = {
+  plans: BillingPlan[];
+  capabilities: {
+    subscription_status: boolean;
+    credit_balance: boolean;
+    invoices: boolean;
+    checkout: boolean;
+  };
+  source: string;
+  note?: string;
+};
+
+export type BillingSubscription = {
+  billing_preference: string;
+  subscriptions: Array<{
+    subscription?: {
+      id?: number;
+      status?: string;
+      amount_total?: number;
+      amount_used?: number;
+      start_time?: number;
+      end_time?: number;
+      next_reset_time?: number;
+      member_level?: string;
+    };
+  }>;
+  all_subscriptions: Array<Record<string, unknown>>;
+  subscription_points: Record<
+    string,
+    {
+      available_points?: number;
+      total_points?: number;
+      used_points?: number;
+    }
+  >;
+};
+
+export type BillingCredits = {
+  wallets: Array<{
+    id: number;
+    source_type: string;
+    points: number;
+    points_total: number;
+    expire_at: number;
+    status: string;
+    priority: number;
+    origin_currency: string;
+    origin_amount: number;
+  }>;
+  balance: number;
+};
+
+export type BillingSubscriptionPlan = {
+  plan: {
+    id: number;
+    title: string;
+    subtitle: string;
+    description: string;
+    price_amount: number;
+    currency: string;
+    price_amount_cny?: number;
+    price_amount_usd?: number;
+    points_amount: number;
+    duration_unit: string;
+    duration_value: number;
+    recommended?: boolean;
+    member_level?: string;
+    total_amount?: number;
+    quota_reset_period?: string;
+  };
+};
+
+export type BillingSubscriptionPlans = {
+  items: BillingSubscriptionPlan[];
+};
+
+export type BillingPointsPackage = {
+  id: number;
+  name: string;
+  currency: string;
+  price_amount: number;
+  points_amount: number;
+  bonus_points: number;
+  enabled: boolean;
+};
+
+export type BillingPointsPackages = {
+  items: BillingPointsPackage[];
+};
+
+export type BillingCheckoutResult = {
+  message?: string;
+  trade_no?: string;
+  url?: string;
+  code_url?: string;
+  data?: Record<string, unknown>;
+};
+
+export type BillingOrderPage = {
+  page: number;
+  page_size: number;
+  total: number;
+  items: Array<Record<string, unknown>>;
+};
+
+export type BillingInvoices = {
+  subscription_orders: BillingOrderPage;
+  point_orders: BillingOrderPage;
+};
+
+export type GatewayBindResponse = {
+  gateway_user_id: number;
+  gateway_username?: string;
+  gateway_display_name?: string;
+  gateway_email?: string;
+  gateway_bound: boolean;
+};
+
 export class PopiartApiError extends Error {
   status: number;
   code?: string;
@@ -221,3 +367,70 @@ export async function getBudgetUsage() {
   }
   return popiartRequest<BudgetUsage>("/budget/usage", { token });
 }
+
+export async function getProjects() {
+  const token = await getSessionToken();
+  if (!token) {
+    return null;
+  }
+  return popiartRequest<ProjectListResponse>("/projects", { token });
+}
+
+export async function getBillingCatalog() {
+  return popiartRequest<BillingCatalog>("/billing/catalog");
+}
+
+export async function getBillingSubscription() {
+  const token = await getSessionToken();
+  if (!token) {
+    return null;
+  }
+  return popiartRequest<BillingSubscription>("/billing/subscription", { token });
+}
+
+export async function getBillingCredits() {
+  const token = await getSessionToken();
+  if (!token) {
+    return null;
+  }
+  return popiartRequest<BillingCredits>("/billing/credits", { token });
+}
+
+export async function getBillingSubscriptionPlans() {
+  const token = await getSessionToken();
+  if (!token) {
+    return null;
+  }
+  return popiartRequest<BillingSubscriptionPlans>("/billing/subscription/plans", { token });
+}
+
+export async function getBillingPointsPackages() {
+  const token = await getSessionToken();
+  if (!token) {
+    return null;
+  }
+  return popiartRequest<BillingPointsPackages>("/billing/points/packages", { token });
+}
+
+export async function getBillingInvoices(options?: {
+  keyword?: string;
+  page?: number;
+  pageSize?: number;
+}) {
+  const token = await getSessionToken();
+  if (!token) {
+    return null;
+  }
+  const query = new URLSearchParams();
+  if (options?.keyword) {
+    query.set("keyword", options.keyword);
+  }
+  if (options?.page && options.page > 0) {
+    query.set("p", String(options.page));
+  }
+  if (options?.pageSize && options.pageSize > 0) {
+    query.set("page_size", String(options.pageSize));
+  }
+  const suffix = query.toString();
+  return popiartRequest<BillingInvoices>(`/billing/invoices${suffix ? `?${suffix}` : ""}`, { token });
+}