feat(notes): make incoming-note popup attention-grabbing

Task #409: incoming notes now mirror UpcomingMeetingAlert's attention model
so recipients can't miss them.

Changes:
- DB: add `notification_sound_note` (default "knock"), `notify_notes_enabled`,
  `vibration_enabled_note` to users schema; pushed via drizzle.
- API spec: add 3 new fields to AuthUser + UpdateNotificationPreferencesBody;
  regenerated codegen.
- Auth route: include new fields in buildAuthUser + PATCH allowlist.
- Socket hook: play notification sound + vibrate on `note_received`,
  gated by mute/notifyNotesEnabled/socket warmup, with playedNoteIdsRef
  dedupe (mirrors upcoming-meeting-alert playedRef).
- IncomingNotePopupContext: enqueue() now returns boolean acceptance so
  the socket hook can suppress sound on own-note/duplicate.
- Popup visual: z-[110], ring-4 amber, shadow-2xl, animate-in zoom,
  avatar animate-ping pulse.
- Settings UI: refactored to SLOT_KEYS map, added 3rd "Notes" slot tab
  (grid-cols-3) with enabled/vibration toggles + sound picker.
- Locales en/ar: added notifSettings.slot.note, notesEnabled, vibrationNote.

Pre-existing typecheck errors in executive-meetings.ts (font settings
scope) are unrelated to this task.

lib/api-spec/openapi.yaml

@@ -3209,14 +3209,20 @@ components:
           $ref: "#/components/schemas/NotificationSoundId"
         notificationSoundMeeting:
           $ref: "#/components/schemas/NotificationSoundId"
+        notificationSoundNote:
+          $ref: "#/components/schemas/NotificationSoundId"
         notifyOrdersEnabled:
           type: boolean
         notifyMeetingsEnabled:
           type: boolean
+        notifyNotesEnabled:
+          type: boolean
         vibrationEnabledOrder:
           type: boolean
         vibrationEnabledMeeting:
           type: boolean
+        vibrationEnabledNote:
+          type: boolean
         notificationsMuted:
           type: boolean
 
@@ -3258,14 +3264,20 @@ components:
           $ref: "#/components/schemas/NotificationSoundId"
         notificationSoundMeeting:
           $ref: "#/components/schemas/NotificationSoundId"
+        notificationSoundNote:
+          $ref: "#/components/schemas/NotificationSoundId"
         notifyOrdersEnabled:
           type: boolean
         notifyMeetingsEnabled:
           type: boolean
+        notifyNotesEnabled:
+          type: boolean
         vibrationEnabledOrder:
           type: boolean
         vibrationEnabledMeeting:
           type: boolean
+        vibrationEnabledNote:
+          type: boolean
         notificationsMuted:
           type: boolean
         roles:
@@ -3287,10 +3299,13 @@ components:
         - isActive
         - notificationSoundOrder
         - notificationSoundMeeting
+        - notificationSoundNote
         - notifyOrdersEnabled
         - notifyMeetingsEnabled
+        - notifyNotesEnabled
         - vibrationEnabledOrder
         - vibrationEnabledMeeting
+        - vibrationEnabledNote
         - notificationsMuted
         - roles
         - groups