Stage 8 polish: profile validation, finished-game UI, badge + Safari fixes

Owner-review follow-up on the Stage 8 branch:
- Friend code is copyable (📋 + toast). The lobby notification badge is fixed —
  it had inherited the hamburger-bar style — into a proper round count dot.
- Safari: min-width:0 on flex text inputs (friend code, profile, chat) so they
  shrink instead of pushing the adjacent button off-screen.
- Profile editing is validated on both the UI and the backend: display-name format
  (letters joined by single space/./_ separators, no leading/trailing/adjacent
  separators, <=32 runes), a UTC-offset timezone picker (account.ResolveZone parses
  ±HH:MM or a legacy IANA name), a 10-minute away grid capped at 12h (wrap-aware),
  and email format; Save is disabled and invalid fields red-bordered until valid.
  Language stays in Settings.
- In a game, an "add to friends" menu item flips to a disabled "request sent"; chat
  send/nudge became ⬆️/🛎️ icon buttons.
- A finished game drops its last-word highlight, hides Check word / Drop game,
  disables zoom, and draws an inert (greyed) footer instead of hiding it.

Tests: account validators (name/away/zone), UI profileValidation, e2e for the
finished-game footer/menu and the copy control. Docs (PLAN, ARCHITECTURE,
FUNCTIONAL +ru, UI_DESIGN) updated for the display-name rule, UTC-offset timezone
and the 12h away window.

docs/ARCHITECTURE.md

@@ -298,11 +298,15 @@ requires (there is no DM surface; chat is per-game).
   the opponent may nudge **once per hour per game**; it is not allowed on one's own
   turn. The platform-native delivery is wired with the gateway / platform
   side-service (Stage 6 / 8).
-- **Profile**: `preferred_language` (en/ru), display name, email
-  (confirm-code binding, see §4), **timezone** (drives the away window and the
-  robot's sleep; user-editable), the daily **away window** and the block toggles —
-  all editable through `account.UpdateProfile`. Linked platform accounts and merge
-  are Stage 11.
+- **Profile**: `preferred_language` (en/ru, edited in Settings), display name, email
+  (confirm-code binding, see §4), **timezone**, the daily **away window** and the
+  block toggles — all editable through `account.UpdateProfile`, which validates them
+  (Stage 8): a display name is Unicode letters joined by single ` `/`.`/`_`
+  separators (no leading/trailing/adjacent separators, ≤ 32 runes); the timezone is a
+  fixed `±HH:MM` **UTC offset** (or a legacy IANA name) resolved by `account.ResolveZone`
+  for the sweeper and the robot's sleep (a fixed offset trades DST for a simple
+  picker); the away window is at most **12 h** (midnight-wrap aware). Linked platform
+  accounts and merge are Stage 11.
 
 ## 9. Persistence
 

docs/FUNCTIONAL.md

@@ -88,9 +88,11 @@ existing friendship). Per-game chat is for quick reactions: messages are short
 even disguised. Nudge the player whose turn is awaited at most once per hour (the
 nudge is part of the game chat); the out-of-app push is delivered via the platform.
 
-### Profile & settings *(Stage 4)*
-Edit language (en/ru), display name, timezone, the daily away window and the block
-toggles, and bind an email by confirm-code: the backend emails a short code that,
+### Profile & settings *(Stage 4 / 8)*
+Edit the display name (letters joined by single space / "." / "_" separators, up to
+32 characters), the timezone (chosen as a UTC offset), the daily away window (on a
+10-minute grid, at most 12 hours, wrapping midnight) and the block toggles, and bind
+an email by confirm-code: the backend emails a short code that,
 once entered, attaches the email to the account (an email already confirmed by
 another account cannot be taken — that is a merge, a later stage). Linked platform
 accounts and merge arrive in Stage 11.

docs/FUNCTIONAL_ru.md

@@ -90,10 +90,12 @@ session-токен; backend сопоставляет его с внутренн
 соперника — не чаще раза в час (nudge — часть игрового чата); внеприложенческий
 push доставляется через платформу.
 
-### Профиль и настройки *(Stage 4)*
-Редактирование языка (en/ru), отображаемого имени, таймзоны, суточного окна
-отсутствия (away) и переключателей блокировок, а также привязка email по
-confirm-коду: backend шлёт на почту короткий код, и после ввода email
+### Профиль и настройки *(Stage 4 / 8)*
+Редактирование отображаемого имени (буквы, разделённые одиночными пробелом / «.» /
+«_», до 32 символов), таймзоны (выбор смещения от UTC), суточного окна отсутствия
+(away; сетка по 10 минут, не более 12 часов, с переходом через полночь) и
+переключателей блокировок, а также привязка email по confirm-коду: backend шлёт на
+почту короткий код, и после ввода email
 привязывается к аккаунту (email, уже подтверждённый другим аккаунтом, занять
 нельзя — это слияние, отдельный этап). Привязанные платформенные аккаунты и
 слияние появятся в Stage 11.

docs/UI_DESIGN.md

@@ -95,13 +95,23 @@ IV 🏅; active games show Your move 🟢 / Opponent's move ⏳; invitations use
 - **Statistics** (`screens/Stats.svelte`, the lobby 📊 tab): a 2-column grid of stat
   cards (wins / losses / draws / games / win-rate / best game / best move) — pure
   numbers, no charts.
-- **Profile editing** (`screens/Profile.svelte`): an inline form (display name, timezone,
-  the away-window time pickers, block toggles) and an email-binding sub-flow (enter email
-  → enter the confirm code). Interface language stays in **Settings** (it writes through
-  to the account for durable users).
+- **Profile editing** (`screens/Profile.svelte`): an inline form — display name, a
+  **UTC-offset** timezone dropdown (defaulting to the browser's offset), the away
+  window as hour + 10-minute dropdowns (24-hour, ≤ 12 h), and block toggles — plus an
+  email-binding sub-flow (enter email → enter the confirm code on a numeric field).
+  Invalid fields show a **red border** (no message) and **Save stays disabled** until
+  every field is valid. Interface language stays in **Settings** (it writes through to
+  the account for durable users).
+- **Friend code**: the issued code sits next to a 📋 copy control; tapping the code or
+  the icon copies it. Flex text inputs carry `min-width:0` so they shrink instead of
+  overflowing in Safari.
 - **History / GCG**: the in-game slide-down history gains the running total per move;
   *Export GCG* shares or downloads the `.gcg` file and appears only once the game is
   finished.
+- **Finished game**: the board keeps no last-word highlight and no zoom; the menu drops
+  *Check word* and *Drop game*; and the footer (rack + tab bar) is **drawn but inert**
+  (greyed, non-interactive) rather than hidden, so the layout does not jump. Chat
+  send / nudge are the ⬆️ / 🛎️ icons.
 
 ## Caveat