Badges: per-badge locked font sizes via cfg_json

Allows coordinators to pre-tune font sizes for attendees with long names
and have those sizes apply automatically on every kiosk, not just one machine.

- ae_types.ts: add cfg_json to ae_EventBadge interface
- db_events.ts: add cfg_json to Badge Dexie interface
- ae_events__event_badge.ts: add cfg_json to properties_to_save so it is
  persisted to IndexedDB on load and returned by the API
- print/+page.svelte: on first load per badge, read cfg_json.font_sizes and
  initialize font_size_name/title/affiliations/location state from saved values
  (guarded by _font_sizes_loaded_for to avoid clobbering user adjustments on
  background liveQuery refreshes)
- ae_comp__badge_print_controls.svelte: add lock_font_sizes() and
  reset_font_sizes_to_auto() functions; add Lock Sizes / Auto reset UI in the
  Staff adjustments section (trusted-only); button shows warning style when
  sizes are unsaved vs success when locked; status indicator shows what is
  currently locked

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/lib/ae_events/ae_events__event_badge.ts

@@ -632,6 +632,7 @@ export const properties_to_save = [
     'print_last_datetime',
     'allow_tracking',
     'agree_to_tc',
+    'cfg_json',
     'other_1_code',
     'other_2_code',
     'other_3_code',

src/lib/ae_events/db_events.ts

@@ -170,6 +170,7 @@ export interface Badge {
 
     // passcode?: null|string;
 
+    cfg_json?: null | string;
     // data_json?: null|string;
 
     default_qry_str?: null | string;