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.

deploy/.env.example

@@ -29,7 +29,9 @@ GM_BASICAUTH_HASH=                     # required; `caddy hash-password` bcrypt
 
 # --- UI build args (baked into the gateway image) ---------------------------
 VITE_TELEGRAM_BOT_ID=
-VITE_TELEGRAM_LINK=
+VITE_TELEGRAM_LINK=                                 # fallback friend-invite Mini App link (per-bot below)
+VITE_TELEGRAM_LINK_EN=                              # friend-invite Mini App link, English bot (full URL, e.g. https://t.me/<bot>/<app>)
+VITE_TELEGRAM_LINK_RU=                              # friend-invite Mini App link, Russian bot (full URL)
 VITE_TELEGRAM_GAME_CHANNEL_NAME_EN=                 # landing "Play in Telegram" link, English bot
 VITE_TELEGRAM_GAME_CHANNEL_NAME_RU=                 # landing "Play in Telegram" link, Russian bot
 VITE_GATEWAY_URL=

deploy/README.md

@@ -84,7 +84,9 @@ connector **fails at boot** if both are empty.
 | `TELEGRAM_API_BASE_URL` | variable | _(empty)_ | Override the Bot API host (a mock/self-hosted server); empty = `https://api.telegram.org`. |
 | `GATEWAY_DEFAULT_SUPPORTED_LANGUAGES` | variable | `en,ru` | Variant-gating set for non-Telegram logins (web/email/guest). |
 | `VITE_TELEGRAM_BOT_ID` | variable | _(empty)_ | UI build-arg: numeric bot id for the web Login Widget. |
-| `VITE_TELEGRAM_LINK` | variable | _(empty)_ | UI build-arg: deep-link base for share-to-Telegram (e.g. `https://t.me/<bot>/<app>`). |
+| `VITE_TELEGRAM_LINK` | variable | _(empty)_ | UI build-arg: **fallback** friend-invite Mini App link (e.g. `https://t.me/<bot>/<app>`), used when the per-bot link below is unset. |
+| `VITE_TELEGRAM_LINK_EN` | variable | _(empty)_ | UI build-arg: friend-invite Mini App link for the **English** bot (full URL, `https://t.me/<bot>/<app>` — `<app>` is the Mini App short name from BotFather). The friend-code share uses the link matching the bot the player signed in through. |
+| `VITE_TELEGRAM_LINK_RU` | variable | _(empty)_ | UI build-arg: same for the **Russian** bot. |
 | `VITE_TELEGRAM_GAME_CHANNEL_NAME_EN` | variable | _(empty)_ | UI build-arg: the landing "Play in Telegram" link for the **English** bot (e.g. `https://t.me/Scrabble_Game`). |
 | `VITE_TELEGRAM_GAME_CHANNEL_NAME_RU` | variable | _(empty)_ | UI build-arg: the landing "Play in Telegram" link for the **Russian** bot (e.g. `https://t.me/Erudit_Game`). |
 | `VITE_GATEWAY_URL` | variable | _(empty)_ | UI build-arg: gateway origin; empty = same-origin (the usual single-origin deploy). |

deploy/docker-compose.yml

@@ -121,6 +121,8 @@ services:
       args:
         VITE_TELEGRAM_BOT_ID: ${VITE_TELEGRAM_BOT_ID:-}
         VITE_TELEGRAM_LINK: ${VITE_TELEGRAM_LINK:-}
+        VITE_TELEGRAM_LINK_EN: ${VITE_TELEGRAM_LINK_EN:-}
+        VITE_TELEGRAM_LINK_RU: ${VITE_TELEGRAM_LINK_RU:-}
         VITE_TELEGRAM_GAME_CHANNEL_NAME_EN: ${VITE_TELEGRAM_GAME_CHANNEL_NAME_EN:-}
         VITE_TELEGRAM_GAME_CHANNEL_NAME_RU: ${VITE_TELEGRAM_GAME_CHANNEL_NAME_RU:-}
         VITE_GATEWAY_URL: ${VITE_GATEWAY_URL:-}
@@ -169,6 +171,8 @@ services:
       args:
         VITE_TELEGRAM_BOT_ID: ${VITE_TELEGRAM_BOT_ID:-}
         VITE_TELEGRAM_LINK: ${VITE_TELEGRAM_LINK:-}
+        VITE_TELEGRAM_LINK_EN: ${VITE_TELEGRAM_LINK_EN:-}
+        VITE_TELEGRAM_LINK_RU: ${VITE_TELEGRAM_LINK_RU:-}
         VITE_TELEGRAM_GAME_CHANNEL_NAME_EN: ${VITE_TELEGRAM_GAME_CHANNEL_NAME_EN:-}
         VITE_TELEGRAM_GAME_CHANNEL_NAME_RU: ${VITE_TELEGRAM_GAME_CHANNEL_NAME_RU:-}
         VITE_GATEWAY_URL: ${VITE_GATEWAY_URL:-}