feat(ui): real friend-invite share with a per-bot link

The friend-code 'share' was an <a> that just opened the bot. Make it a real share:
Telegram's native share-to-chat picker inside the Mini App (openTelegramLink +
t.me/share/url), the system share sheet (navigator.share) on the web, else copy the
link. The shared deep link points at the same bot the player is in — it picks
VITE_TELEGRAM_LINK_EN/_RU by the session's service language, falling back to the
single VITE_TELEGRAM_LINK. Adds the per-bot build args across Dockerfile / compose /
ci.yaml / .env / docs; PLAN TODO-5 updated.

ui/README.md

@@ -28,8 +28,11 @@ pnpm codegen      # regenerate src/gen from edge.proto + scrabble.fbs (dev-time)
 `GATEWAY_URL` overrides the dev proxy target; `VITE_GATEWAY_URL` sets the runtime
 gateway origin for a packaged (non-proxied) build. `VITE_TELEGRAM_BOT_ID`
 enables the "Link Telegram" web sign-in (the Login Widget) — inert until the site
-domain is registered with BotFather (`/setdomain`); `VITE_TELEGRAM_LINK` is the
-share-to-Telegram deep-link base. `VITE_TELEGRAM_GAME_CHANNEL_NAME_EN` / `VITE_TELEGRAM_GAME_CHANNEL_NAME_RU`
+domain is registered with BotFather (`/setdomain`); `VITE_TELEGRAM_LINK_EN` /
+`VITE_TELEGRAM_LINK_RU` are the per-bot friend-invite Mini App links (full URL
+`https://t.me/<bot>/<app>`; the share picks the one matching the bot the player
+signed in through, falling back to `VITE_TELEGRAM_LINK`).
+`VITE_TELEGRAM_GAME_CHANNEL_NAME_EN` / `VITE_TELEGRAM_GAME_CHANNEL_NAME_RU`
 are the per-language "Play in Telegram" links shown on the landing page.
 
 The build has **two entries**: the game SPA (`index.html`, served at `/app/` and

ui/src/lib/deeplink.test.ts

@@ -35,4 +35,17 @@ describe('shareLink', () => {
     vi.stubEnv('VITE_TELEGRAM_LINK', 'https://t.me/bot/app');
     expect(shareLink('f123456')).toBe('https://t.me/bot/app?startapp=f123456');
   });
+
+  it('picks the per-bot base by language', () => {
+    vi.stubEnv('VITE_TELEGRAM_LINK_EN', 'https://t.me/enbot/app');
+    vi.stubEnv('VITE_TELEGRAM_LINK_RU', 'https://t.me/rubot/app');
+    expect(shareLink('f1', 'en')).toBe('https://t.me/enbot/app?startapp=f1');
+    expect(shareLink('f1', 'ru')).toBe('https://t.me/rubot/app?startapp=f1');
+  });
+
+  it('falls back to the language-agnostic base when the per-bot one is unset', () => {
+    vi.stubEnv('VITE_TELEGRAM_LINK', 'https://t.me/fallback/app');
+    vi.stubEnv('VITE_TELEGRAM_LINK_RU', '');
+    expect(shareLink('f1', 'ru')).toBe('https://t.me/fallback/app?startapp=f1');
+  });
 });

ui/src/lib/deeplink.ts

@@ -36,13 +36,29 @@ export const invitationParam = (id: string): string => 'i' + id;
 /** friendCodeParam builds the start parameter that redeems a friend code. */
 export const friendCodeParam = (code: string): string => 'f' + code;
 
+function envVar(name: string): string | undefined {
+  return (import.meta.env as Record<string, string | undefined>)[name];
+}
+
 /**
- * shareLink wraps a deep-link start parameter in a t.me Mini App link, using the
- * VITE_TELEGRAM_LINK base (e.g. https://t.me/<bot>/<app>). It returns null when the
- * base is not configured, so callers can hide the share affordance.
+ * telegramBase returns the Mini App link base (e.g. https://t.me/<bot>/<app>) for a
+ * bot language: VITE_TELEGRAM_LINK_EN / _RU when lang is en/ru, else the
+ * language-agnostic VITE_TELEGRAM_LINK. Returns null when none is configured, so a
+ * shared link points at the same bot the player signed in through.
  */
-export function shareLink(param: string): string | null {
-  const base = import.meta.env.VITE_TELEGRAM_LINK as string | undefined;
+function telegramBase(lang: string): string | null {
+  const byLang =
+    lang === 'ru' ? envVar('VITE_TELEGRAM_LINK_RU') : lang === 'en' ? envVar('VITE_TELEGRAM_LINK_EN') : undefined;
+  return byLang || envVar('VITE_TELEGRAM_LINK') || null;
+}
+
+/**
+ * shareLink wraps a deep-link start parameter in a t.me Mini App link for the given
+ * bot language (the session's service language). Returns null when no base is
+ * configured, so callers can hide the share affordance.
+ */
+export function shareLink(param: string, lang = ''): string | null {
+  const base = telegramBase(lang);
   if (!base) return null;
   const sep = base.includes('?') ? '&' : '?';
   return `${base}${sep}startapp=${encodeURIComponent(param)}`;

ui/src/lib/i18n/en.ts

@@ -234,6 +234,8 @@ export const en = {
   'friends.copy': 'Copy',
   'friends.codeCopied': 'Code copied.',
   'friends.shareTelegram': 'Share via Telegram',
+  'friends.inviteText': "Let's be friends in Scrabble!",
+  'friends.linkCopied': 'Link copied.',
   'friends.added': 'Added {name}.',
   'friends.blockedList': 'Blocked players',
   'friends.unblock': 'Unblock',

ui/src/lib/i18n/ru.ts

@@ -235,6 +235,8 @@ export const ru: Record<MessageKey, string> = {
   'friends.copy': 'Копировать',
   'friends.codeCopied': 'Код скопирован.',
   'friends.shareTelegram': 'Поделиться через Telegram',
+  'friends.inviteText': 'Давай дружить в Скрэббл!',
+  'friends.linkCopied': 'Ссылка скопирована.',
   'friends.added': 'Добавлен(а) {name}.',
   'friends.blockedList': 'Заблокированные',
   'friends.unblock': 'Разблокировать',

ui/src/lib/telegram.ts

@@ -15,6 +15,7 @@ interface TelegramWebApp {
   contentSafeAreaInset?: { top: number; bottom: number; left: number; right: number };
   ready?: () => void;
   expand?: () => void;
+  openTelegramLink?: (url: string) => void;
   onEvent?: (event: string, handler: () => void) => void;
   setHeaderColor?: (color: string) => void;
   setBackgroundColor?: (color: string) => void;
@@ -49,6 +50,19 @@ export function insideTelegram(): boolean {
   return !!w && typeof w.initData === 'string' && w.initData.length > 0;
 }
 
+/**
+ * shareTelegramLink opens Telegram's native "share to a chat" picker for url with a
+ * caption, through the Mini App SDK (https://t.me/share/url). Returns false outside
+ * Telegram or when the SDK lacks the method, so the caller can fall back to the Web
+ * Share API. Works consistently on iOS and Android within Telegram.
+ */
+export function shareTelegramLink(url: string, text: string): boolean {
+  const w = webApp();
+  if (!w?.openTelegramLink) return false;
+  w.openTelegramLink(`https://t.me/share/url?url=${encodeURIComponent(url)}&text=${encodeURIComponent(text)}`);
+  return true;
+}
+
 /** TelegramLaunch is the data a Mini App launch carries. */
 export interface TelegramLaunch {
   initData: string;

ui/src/screens/Friends.svelte

@@ -5,6 +5,7 @@
   import { gateway } from '../lib/gateway';
   import { t } from '../lib/i18n/index.svelte';
   import { friendCodeParam, shareLink } from '../lib/deeplink';
+  import { shareTelegramLink } from '../lib/telegram';
   import type { AccountRef, FriendCode } from '../lib/model';
 
   let friends = $state<AccountRef[]>([]);
@@ -78,6 +79,28 @@
       // Clipboard may be unavailable (insecure context); leave the code on screen.
     }
   }
+
+  // shareInvite shares the friend-code deep link: inside Telegram via the native
+  // "share to chat" picker; on the web via the system share sheet; failing both, it
+  // copies the link to the clipboard.
+  async function shareInvite(url: string) {
+    const text = t('friends.inviteText');
+    if (shareTelegramLink(url, text)) return;
+    if (typeof navigator !== 'undefined' && navigator.share) {
+      try {
+        await navigator.share({ text, url });
+        return;
+      } catch {
+        return; // the user dismissed the share sheet
+      }
+    }
+    try {
+      await navigator.clipboard.writeText(url);
+      showToast(t('friends.linkCopied'));
+    } catch {
+      // Clipboard unavailable (insecure context); nothing more to do.
+    }
+  }
 </script>
 
 <div class="page">
@@ -97,7 +120,7 @@
         <button class="btn" onclick={redeem} disabled={!connection.online}>{t('friends.redeem')}</button>
       </div>
       {#if code}
-        {@const tg = shareLink(friendCodeParam(code.code))}
+        {@const tg = shareLink(friendCodeParam(code.code), app.session?.serviceLanguage || app.locale)}
         <div class="code" data-testid="friend-code">
           <div class="coderow">
             <button class="codeval" onclick={copyCode}>{code.code}</button>
@@ -107,7 +130,7 @@
             {t('friends.codeHint')} · {t('friends.codeExpires', { time: codeTime(code.expiresAtUnix) })}
           </span>
           {#if tg}
-            <a class="link tgshare" href={tg} target="_blank" rel="noopener">{t('friends.shareTelegram')}</a>
+            <button type="button" class="link tgshare" onclick={() => shareInvite(tg)}>{t('friends.shareTelegram')}</button>
           {/if}
         </div>
       {:else}