feat: file variety, user status, DND gate, drag-drop, mentions, link preview, emoji picker, soundboard, ringtone

Attachments
- Video: native <video controls>, decrypted blob, metadata preload
- PDF: collapsible <object> viewer with download + preview toggle
- Generic: file card with lazy decrypt, mime-to-extension map
- MessageBubble dispatch: audio/image/video/pdf/generic by mime
- Composer accept widened from image/* to any; AttachmentPreview renders
  non-images as file cards

User status
- usePeerPresence returns { state, statusMessage } and tracks both fields
  via realtime updates
- ConversationHeader subtitle shows custom status_message when peer is
  online/idle/dnd (with message set); falls back to localized presence
  label; always "Offline" when state === 'offline'
- UserBar: status_message input in dropdown (max 128 chars, save on
  blur/Enter), subtitle uses same precedence as peer view
- AuthContext: auto-flip offline → online on session mount; best-effort
  offline on beforeunload/pagehide; respects explicit idle/dnd/invisible
- i18n: presence.status_placeholder (DE + EN)

DND
- CallUI: incoming ring suppressed when own presence === 'dnd' (outgoing
  rings stay audible — user-initiated)
- CallContext: presenceRef mirrors profile.presenceState, incoming-call
  and missed-call OS notifications skipped under DND
- ConversationsContext already gated message tone + notify

Drag/drop + paste
- Page-root drag handlers feed ingestFiles; overlay shown while dragging
- Textarea onPaste extracts clipboard image items

@mentions in groups
- MentionAutocomplete: keyboard-driven dropdown, arrow/enter/tab/esc
- Composer onChange parses trailing @token, auto-open
- renderBodyWithMentions highlights @username tokens in bubbles

Link previews
- Migration 20260421000003_link_previews.sql (cache table, auth read,
  service-role write via edge function)
- Edge function og-preview: POST {url}, fetches HTML (6s timeout, 1MB
  cap), regex-parses OG/twitter/description, upserts cache
- useLinkPreview hook with in-memory cache + inflight dedup
- LinkPreviewCard rendered from first URL in message body

Emoji picker
- Built-in curated set (~250 emojis) across five categories
- Search by keyword/emoji char/category, recent list persisted in
  localStorage
- Trigger button next to + and voice buttons in composer

Soundboard + ringtone + mic pipeline
- Pulled in (user-authored) SoundboardManagerDialog/Panel/Settings,
  RingtoneSettings, mic pipeline + hotkeys + storage modules
- AuthContext imports updateOwnProfile for presence auto-flip

Fixes
- AttachmentAudio min-width so bubbles don't collapse to 0px on peer
  side
- Focus flicker: visibility/online wake refresh throttled to 30s,
  focus listener dropped, loading flag only on first fetch

apps/desktop/src/components/CallControls.tsx

@@ -7,6 +7,7 @@ import {
   MicOffIcon,
   MonitorShareIcon,
   MonitorStopIcon,
+  MusicIcon,
   PhoneOffIcon,
   UsersIcon,
   VideoIcon,
@@ -23,6 +24,9 @@ interface Props {
   onToggleDeafen: () => void;
   onHangup: () => void;
   onOpenParticipants?: () => void;
+  /** Toggle the in-call soundboard popover. Active = panel currently open. */
+  onToggleSoundboard?: () => void;
+  soundboardOpen?: boolean;
   /** Compact variant used inside the docked call (36px buttons). */
   compact?: boolean;
   /** Glass variant used when controls float on fullscreen cinema mode. */
@@ -42,6 +46,8 @@ export function CallControls({
   onToggleDeafen,
   onHangup,
   onOpenParticipants,
+  onToggleSoundboard,
+  soundboardOpen = false,
   compact = false,
   glass = false,
   disabledMedia = false,
@@ -115,6 +121,18 @@ export function CallControls({
           <MonitorShareIcon className="h-5 w-5" />
         )}
       </CallButton>
+      {onToggleSoundboard && (
+        <CallButton
+          label={t('app:soundboard.toggle', { defaultValue: 'Soundboard' })}
+          active={soundboardOpen}
+          activeTone="accent"
+          onClick={onToggleSoundboard}
+          glass={glass}
+          className={btnSize}
+        >
+          <MusicIcon className="h-5 w-5" />
+        </CallButton>
+      )}
       {onOpenParticipants && (
         <CallButton
           label={t('app:call.participants', { defaultValue: 'Teilnehmer' })}