Stage 8: UI social/account/history surfaces

Wire the deferred Stage 7 surfaces end-to-end (UI -> gateway transcode ->
backend REST -> existing domain services): friends (incl. one-time friend
codes), per-user blocks, friend-game invitations, profile editing + email
binding, the statistics screen, and the in-game history + GCG export.

Friends gain two add paths (interview decision, a deliberate plan change):
one-time 6-digit codes (friend_codes table, 12h TTL, single-use, rate-limited
redeem); and play-gated requests (shared game required) where an explicit
decline is permanent, an ignored request lapses after 30 days, and a code
bypasses a decline. Migration 00006 widens friendships_status_chk and adds
friend_codes.

Lobby notification badge is poll + push: a new generic `notify` event drives
it live; the client polls on open/focus. Language stays a single Settings
control that writes through to the durable account's preferred_language. GCG
export is finished-only (game.ErrGameActive) and shares/downloads the .gcg file.

Tests: backend unit + inttest (friend gate/decline/code, ListInvitations,
GetStats, GCG gate), gateway transcode round-trips + notify constructor, UI
vitest (codecs, win-rate, share choice) + Playwright social specs. Docs: PLAN
(Stage 8 done + refinements + TODO-5), ARCHITECTURE, FUNCTIONAL(+ru), UI_DESIGN,
TESTING, module READMEs.

ui/src/lib/i18n/en.ts

@@ -102,7 +102,21 @@ export const en = {
   'profile.timezone': 'Time zone',
   'profile.hintBalance': 'Hint balance',
   'profile.guest': 'Guest account',
-  'profile.readonly': 'Editing your profile arrives in a later update.',
+  'profile.edit': 'Edit profile',
+  'profile.displayName': 'Display name',
+  'profile.awayWindow': 'Away window',
+  'profile.awayHint': 'You are not auto-resigned during these hours.',
+  'profile.from': 'From',
+  'profile.to': 'To',
+  'profile.blockChat': 'Disable chat',
+  'profile.blockFriendRequests': 'Disable friend requests',
+  'profile.email': 'Email',
+  'profile.bindEmail': 'Bind email',
+  'profile.emailCode': 'Confirmation code',
+  'profile.emailSent': 'We sent a code to {email}.',
+  'profile.emailBound': 'Email confirmed.',
+  'profile.saved': 'Profile saved.',
+  'profile.guestLocked': 'Sign in with email to manage your profile.',
 
   'settings.title': 'Settings',
   'settings.theme': 'Theme',
@@ -143,6 +157,83 @@ export const en = {
   'error.unavailable': 'Connection problem. Retrying…',
   'error.internal': 'Something went wrong.',
   'error.generic': 'Something went wrong.',
+
+  'lobby.invitations': 'Invitations',
+  'lobby.friends': 'Friends',
+
+  'friends.title': 'Friends',
+  'friends.yours': 'Your friends',
+  'friends.none': 'No friends yet.',
+  'friends.incoming': 'Friend requests',
+  'friends.accept': 'Accept',
+  'friends.decline': 'Decline',
+  'friends.unfriend': 'Remove',
+  'friends.block': 'Block',
+  'friends.add': 'Add a friend',
+  'friends.addFromGame': 'Add to friends',
+  'friends.requestSent': 'Friend request sent.',
+  'friends.getCode': 'Show my code',
+  'friends.codeHint': 'Give this code to a friend within 12 hours.',
+  'friends.codeExpires': 'Expires at {time}',
+  'friends.enterCode': 'Have a code? Add a friend',
+  'friends.codePlaceholder': '6-digit code',
+  'friends.redeem': 'Add',
+  'friends.added': 'Added {name}.',
+  'friends.blockedList': 'Blocked players',
+  'friends.unblock': 'Unblock',
+  'friends.noneBlocked': 'No blocked players.',
+
+  'invitations.none': 'No invitations.',
+  'invitations.from': 'From {name}',
+  'invitations.with': 'With {names}',
+  'invitations.accept': 'Accept',
+  'invitations.decline': 'Decline',
+  'invitations.cancel': 'Cancel',
+  'invitations.waiting': 'Waiting for replies',
+
+  'new.auto': 'Quick match',
+  'new.withFriends': 'Play with friends',
+  'new.pickFriends': 'Choose who to invite',
+  'new.invite': 'Send invitation',
+  'new.moveTime': 'Move time',
+  'new.hintsPerPlayer': 'Hints per player',
+  'new.invited': 'Invitation sent.',
+  'new.noFriends': 'Add friends first to invite them.',
+
+  'stats.title': 'Statistics',
+  'stats.wins': 'Wins',
+  'stats.losses': 'Losses',
+  'stats.draws': 'Draws',
+  'stats.played': 'Games',
+  'stats.winRate': 'Win rate',
+  'stats.maxGame': 'Best game',
+  'stats.maxWord': 'Best move',
+  'stats.guestHint': 'Sign in to track your statistics.',
+
+  'game.exportGcg': 'Export GCG',
+  'game.gcgActiveOnly': 'Available once the game is finished.',
+
+  'time.minutes': '{n} min',
+  'time.hours': '{n} h',
+
+  'error.self_relation': 'You cannot do that to yourself.',
+  'error.request_exists': 'A request or friendship already exists.',
+  'error.request_blocked': 'This player is not accepting requests.',
+  'error.request_not_found': 'No matching friend request.',
+  'error.no_shared_game': 'You can only add someone you have played with.',
+  'error.request_declined': 'This player declined your request.',
+  'error.friend_code_invalid': 'That friend code is invalid or expired.',
+  'error.invalid_invitation': 'Invalid invitation.',
+  'error.invitation_blocked': 'You cannot invite this player.',
+  'error.invitation_not_found': 'Invitation not found.',
+  'error.invitation_not_pending': 'This invitation is no longer open.',
+  'error.invitation_expired': 'This invitation has expired.',
+  'error.not_invited': 'You were not invited.',
+  'error.already_responded': 'You already responded.',
+  'error.not_inviter': 'Only the inviter can do that.',
+  'error.game_active': 'Available only after the game is finished.',
+  'error.invalid_profile': 'Some profile fields are invalid.',
+  'error.already_confirmed': 'This email is already confirmed.',
 } as const;
 
 export type MessageKey = keyof typeof en;