feat(payments): wallet screen with balances, benefits and storefront

Add the "Кошелёк" section to the settings hub: context-visible chip
balances, active benefits (no-ads term/forever, hints) and a storefront of
chip-priced values and money-priced chip packs. Guests have no wallet; the
Google Play build hides the money purchases behind a RuStore stub; a web
purchase that would draw VK/Telegram chips warns first.

Add the catalog read path the storefront needs — a context-projected
GET /api/v1/user/wallet/catalog (payments service + store, gateway op
wallet.catalog, FBS Catalog/CatalogProduct/CatalogAtom, client decode) —
plus the client leg for the existing wallet.get/buy ops. Value spends reuse
the existing spend path; the chip-pack purchase (money order flow) arrives
with payment intake, so its action is a disabled placeholder for now.

Covered by Go unit (catalog projection) + integration (/wallet/catalog over
Postgres), vitest (formatting, spendable selection, web-spend warning, GP
flag, codec + gateway encode round-trips) and Playwright mock e2e (render,
guest-hidden, GP stub, warning) on Chromium + WebKit.

ui/src/gen/fbs/scrabblefb.ts

@@ -11,6 +11,9 @@ export { BestMoveTile } from './scrabblefb/best-move-tile.js';
 export { BestMoveView } from './scrabblefb/best-move-view.js';
 export { BlockList } from './scrabblefb/block-list.js';
 export { BlockStatus } from './scrabblefb/block-status.js';
+export { Catalog } from './scrabblefb/catalog.js';
+export { CatalogAtom } from './scrabblefb/catalog-atom.js';
+export { CatalogProduct } from './scrabblefb/catalog-product.js';
 export { ChatList } from './scrabblefb/chat-list.js';
 export { ChatMessage } from './scrabblefb/chat-message.js';
 export { ChatPostRequest } from './scrabblefb/chat-post-request.js';

ui/src/gen/fbs/scrabblefb/catalog-atom.ts

@@ -0,0 +1,58 @@
+// automatically generated by the FlatBuffers compiler, do not modify
+
+import * as flatbuffers from 'flatbuffers';
+
+export class CatalogAtom {
+  bb: flatbuffers.ByteBuffer|null = null;
+  bb_pos = 0;
+  __init(i:number, bb:flatbuffers.ByteBuffer):CatalogAtom {
+  this.bb_pos = i;
+  this.bb = bb;
+  return this;
+}
+
+static getRootAsCatalogAtom(bb:flatbuffers.ByteBuffer, obj?:CatalogAtom):CatalogAtom {
+  return (obj || new CatalogAtom()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+}
+
+static getSizePrefixedRootAsCatalogAtom(bb:flatbuffers.ByteBuffer, obj?:CatalogAtom):CatalogAtom {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
+  return (obj || new CatalogAtom()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+}
+
+atomType():string|null
+atomType(optionalEncoding:flatbuffers.Encoding):string|Uint8Array|null
+atomType(optionalEncoding?:any):string|Uint8Array|null {
+  const offset = this.bb!.__offset(this.bb_pos, 4);
+  return offset ? this.bb!.__string(this.bb_pos + offset, optionalEncoding) : null;
+}
+
+quantity():number {
+  const offset = this.bb!.__offset(this.bb_pos, 6);
+  return offset ? this.bb!.readInt32(this.bb_pos + offset) : 0;
+}
+
+static startCatalogAtom(builder:flatbuffers.Builder) {
+  builder.startObject(2);
+}
+
+static addAtomType(builder:flatbuffers.Builder, atomTypeOffset:flatbuffers.Offset) {
+  builder.addFieldOffset(0, atomTypeOffset, 0);
+}
+
+static addQuantity(builder:flatbuffers.Builder, quantity:number) {
+  builder.addFieldInt32(1, quantity, 0);
+}
+
+static endCatalogAtom(builder:flatbuffers.Builder):flatbuffers.Offset {
+  const offset = builder.endObject();
+  return offset;
+}
+
+static createCatalogAtom(builder:flatbuffers.Builder, atomTypeOffset:flatbuffers.Offset, quantity:number):flatbuffers.Offset {
+  CatalogAtom.startCatalogAtom(builder);
+  CatalogAtom.addAtomType(builder, atomTypeOffset);
+  CatalogAtom.addQuantity(builder, quantity);
+  return CatalogAtom.endCatalogAtom(builder);
+}
+}

ui/src/gen/fbs/scrabblefb/catalog-product.ts

@@ -0,0 +1,134 @@
+// automatically generated by the FlatBuffers compiler, do not modify
+
+import * as flatbuffers from 'flatbuffers';
+
+import { CatalogAtom } from '../scrabblefb/catalog-atom.js';
+
+
+export class CatalogProduct {
+  bb: flatbuffers.ByteBuffer|null = null;
+  bb_pos = 0;
+  __init(i:number, bb:flatbuffers.ByteBuffer):CatalogProduct {
+  this.bb_pos = i;
+  this.bb = bb;
+  return this;
+}
+
+static getRootAsCatalogProduct(bb:flatbuffers.ByteBuffer, obj?:CatalogProduct):CatalogProduct {
+  return (obj || new CatalogProduct()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+}
+
+static getSizePrefixedRootAsCatalogProduct(bb:flatbuffers.ByteBuffer, obj?:CatalogProduct):CatalogProduct {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
+  return (obj || new CatalogProduct()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+}
+
+kind():string|null
+kind(optionalEncoding:flatbuffers.Encoding):string|Uint8Array|null
+kind(optionalEncoding?:any):string|Uint8Array|null {
+  const offset = this.bb!.__offset(this.bb_pos, 4);
+  return offset ? this.bb!.__string(this.bb_pos + offset, optionalEncoding) : null;
+}
+
+productId():string|null
+productId(optionalEncoding:flatbuffers.Encoding):string|Uint8Array|null
+productId(optionalEncoding?:any):string|Uint8Array|null {
+  const offset = this.bb!.__offset(this.bb_pos, 6);
+  return offset ? this.bb!.__string(this.bb_pos + offset, optionalEncoding) : null;
+}
+
+title():string|null
+title(optionalEncoding:flatbuffers.Encoding):string|Uint8Array|null
+title(optionalEncoding?:any):string|Uint8Array|null {
+  const offset = this.bb!.__offset(this.bb_pos, 8);
+  return offset ? this.bb!.__string(this.bb_pos + offset, optionalEncoding) : null;
+}
+
+chips():number {
+  const offset = this.bb!.__offset(this.bb_pos, 10);
+  return offset ? this.bb!.readInt32(this.bb_pos + offset) : 0;
+}
+
+moneyAmount():bigint {
+  const offset = this.bb!.__offset(this.bb_pos, 12);
+  return offset ? this.bb!.readInt64(this.bb_pos + offset) : BigInt('0');
+}
+
+moneyCurrency():string|null
+moneyCurrency(optionalEncoding:flatbuffers.Encoding):string|Uint8Array|null
+moneyCurrency(optionalEncoding?:any):string|Uint8Array|null {
+  const offset = this.bb!.__offset(this.bb_pos, 14);
+  return offset ? this.bb!.__string(this.bb_pos + offset, optionalEncoding) : null;
+}
+
+atoms(index: number, obj?:CatalogAtom):CatalogAtom|null {
+  const offset = this.bb!.__offset(this.bb_pos, 16);
+  return offset ? (obj || new CatalogAtom()).__init(this.bb!.__indirect(this.bb!.__vector(this.bb_pos + offset) + index * 4), this.bb!) : null;
+}
+
+atomsLength():number {
+  const offset = this.bb!.__offset(this.bb_pos, 16);
+  return offset ? this.bb!.__vector_len(this.bb_pos + offset) : 0;
+}
+
+static startCatalogProduct(builder:flatbuffers.Builder) {
+  builder.startObject(7);
+}
+
+static addKind(builder:flatbuffers.Builder, kindOffset:flatbuffers.Offset) {
+  builder.addFieldOffset(0, kindOffset, 0);
+}
+
+static addProductId(builder:flatbuffers.Builder, productIdOffset:flatbuffers.Offset) {
+  builder.addFieldOffset(1, productIdOffset, 0);
+}
+
+static addTitle(builder:flatbuffers.Builder, titleOffset:flatbuffers.Offset) {
+  builder.addFieldOffset(2, titleOffset, 0);
+}
+
+static addChips(builder:flatbuffers.Builder, chips:number) {
+  builder.addFieldInt32(3, chips, 0);
+}
+
+static addMoneyAmount(builder:flatbuffers.Builder, moneyAmount:bigint) {
+  builder.addFieldInt64(4, moneyAmount, BigInt('0'));
+}
+
+static addMoneyCurrency(builder:flatbuffers.Builder, moneyCurrencyOffset:flatbuffers.Offset) {
+  builder.addFieldOffset(5, moneyCurrencyOffset, 0);
+}
+
+static addAtoms(builder:flatbuffers.Builder, atomsOffset:flatbuffers.Offset) {
+  builder.addFieldOffset(6, atomsOffset, 0);
+}
+
+static createAtomsVector(builder:flatbuffers.Builder, data:flatbuffers.Offset[]):flatbuffers.Offset {
+  builder.startVector(4, data.length, 4);
+  for (let i = data.length - 1; i >= 0; i--) {
+    builder.addOffset(data[i]!);
+  }
+  return builder.endVector();
+}
+
+static startAtomsVector(builder:flatbuffers.Builder, numElems:number) {
+  builder.startVector(4, numElems, 4);
+}
+
+static endCatalogProduct(builder:flatbuffers.Builder):flatbuffers.Offset {
+  const offset = builder.endObject();
+  return offset;
+}
+
+static createCatalogProduct(builder:flatbuffers.Builder, kindOffset:flatbuffers.Offset, productIdOffset:flatbuffers.Offset, titleOffset:flatbuffers.Offset, chips:number, moneyAmount:bigint, moneyCurrencyOffset:flatbuffers.Offset, atomsOffset:flatbuffers.Offset):flatbuffers.Offset {
+  CatalogProduct.startCatalogProduct(builder);
+  CatalogProduct.addKind(builder, kindOffset);
+  CatalogProduct.addProductId(builder, productIdOffset);
+  CatalogProduct.addTitle(builder, titleOffset);
+  CatalogProduct.addChips(builder, chips);
+  CatalogProduct.addMoneyAmount(builder, moneyAmount);
+  CatalogProduct.addMoneyCurrency(builder, moneyCurrencyOffset);
+  CatalogProduct.addAtoms(builder, atomsOffset);
+  return CatalogProduct.endCatalogProduct(builder);
+}
+}

ui/src/gen/fbs/scrabblefb/catalog.ts

@@ -0,0 +1,66 @@
+// automatically generated by the FlatBuffers compiler, do not modify
+
+import * as flatbuffers from 'flatbuffers';
+
+import { CatalogProduct } from '../scrabblefb/catalog-product.js';
+
+
+export class Catalog {
+  bb: flatbuffers.ByteBuffer|null = null;
+  bb_pos = 0;
+  __init(i:number, bb:flatbuffers.ByteBuffer):Catalog {
+  this.bb_pos = i;
+  this.bb = bb;
+  return this;
+}
+
+static getRootAsCatalog(bb:flatbuffers.ByteBuffer, obj?:Catalog):Catalog {
+  return (obj || new Catalog()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+}
+
+static getSizePrefixedRootAsCatalog(bb:flatbuffers.ByteBuffer, obj?:Catalog):Catalog {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
+  return (obj || new Catalog()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+}
+
+products(index: number, obj?:CatalogProduct):CatalogProduct|null {
+  const offset = this.bb!.__offset(this.bb_pos, 4);
+  return offset ? (obj || new CatalogProduct()).__init(this.bb!.__indirect(this.bb!.__vector(this.bb_pos + offset) + index * 4), this.bb!) : null;
+}
+
+productsLength():number {
+  const offset = this.bb!.__offset(this.bb_pos, 4);
+  return offset ? this.bb!.__vector_len(this.bb_pos + offset) : 0;
+}
+
+static startCatalog(builder:flatbuffers.Builder) {
+  builder.startObject(1);
+}
+
+static addProducts(builder:flatbuffers.Builder, productsOffset:flatbuffers.Offset) {
+  builder.addFieldOffset(0, productsOffset, 0);
+}
+
+static createProductsVector(builder:flatbuffers.Builder, data:flatbuffers.Offset[]):flatbuffers.Offset {
+  builder.startVector(4, data.length, 4);
+  for (let i = data.length - 1; i >= 0; i--) {
+    builder.addOffset(data[i]!);
+  }
+  return builder.endVector();
+}
+
+static startProductsVector(builder:flatbuffers.Builder, numElems:number) {
+  builder.startVector(4, numElems, 4);
+}
+
+static endCatalog(builder:flatbuffers.Builder):flatbuffers.Offset {
+  const offset = builder.endObject();
+  return offset;
+}
+
+static createCatalog(builder:flatbuffers.Builder, productsOffset:flatbuffers.Offset):flatbuffers.Offset {
+  Catalog.startCatalog(builder);
+  Catalog.addProducts(builder, productsOffset);
+  return Catalog.endCatalog(builder);
+}
+}