Stage 17 #2: extend the offline soft-disable to all server-action buttons

Following the in-game bar, the Connecting indicator now also visually disables the
other proactive (server-sending) controls while offline: chat send + nudge, profile
save / link email|telegram / merge-confirm, friends (redeem, get-code, accept/decline,
unfriend, block, unblock), New Game (auto-match variant + send-invitation) and the
lobby hide ❌. Purely local controls (board/rack/reset, menus, navigation, settings,
copy-code) stay live. Each reads the global connection.online signal; full e2e + check
green.

ui/src/screens/Friends.svelte

@@ -2,6 +2,7 @@
   import { onMount } from 'svelte';
   import Screen from '../components/Screen.svelte';
   import { app, handleError, refreshNotifications, showToast } from '../lib/app.svelte';
+  import { connection } from '../lib/connection.svelte';
   import { gateway } from '../lib/gateway';
   import { t } from '../lib/i18n/index.svelte';
   import { friendCodeParam, shareLink } from '../lib/deeplink';
@@ -95,7 +96,7 @@
             inputmode="numeric"
             maxlength="6"
           />
-          <button class="btn" onclick={redeem}>{t('friends.redeem')}</button>
+          <button class="btn" onclick={redeem} disabled={!connection.online}>{t('friends.redeem')}</button>
         </div>
         {#if code}
           {@const tg = shareLink(friendCodeParam(code.code))}
@@ -112,7 +113,7 @@
             {/if}
           </div>
         {:else}
-          <button class="link" onclick={getCode}>{t('friends.getCode')}</button>
+          <button class="link" onclick={getCode} disabled={!connection.online}>{t('friends.getCode')}</button>
         {/if}
       </section>
 
@@ -123,8 +124,8 @@
             <div class="item">
               <span class="who">{r.displayName}</span>
               <span class="acts">
-                <button class="btn" onclick={() => respond(r.accountId, true)}>{t('friends.accept')}</button>
-                <button class="ghost" onclick={() => respond(r.accountId, false)}>{t('friends.decline')}</button>
+                <button class="btn" onclick={() => respond(r.accountId, true)} disabled={!connection.online}>{t('friends.accept')}</button>
+                <button class="ghost" onclick={() => respond(r.accountId, false)} disabled={!connection.online}>{t('friends.decline')}</button>
               </span>
             </div>
           {/each}
@@ -138,8 +139,8 @@
             <div class="item">
               <span class="who">{f.displayName}</span>
               <span class="acts">
-                <button class="ghost" onclick={() => remove(f.accountId)}>{t('friends.unfriend')}</button>
-                <button class="ghost danger" onclick={() => blockUser(f.accountId)}>{t('friends.block')}</button>
+                <button class="ghost" onclick={() => remove(f.accountId)} disabled={!connection.online}>{t('friends.unfriend')}</button>
+                <button class="ghost danger" onclick={() => blockUser(f.accountId)} disabled={!connection.online}>{t('friends.block')}</button>
               </span>
             </div>
           {/each}
@@ -154,7 +155,7 @@
           {#each blocked as b (b.accountId)}
             <div class="item">
               <span class="who">{b.displayName}</span>
-              <button class="ghost" onclick={() => unblock(b.accountId)}>{t('friends.unblock')}</button>
+              <button class="ghost" onclick={() => unblock(b.accountId)} disabled={!connection.online}>{t('friends.unblock')}</button>
             </div>
           {/each}
         </section>