WebAuthn biometric + PWA widget + UI header fixes + mobile responsive

- WebAuthn: register/auth options, device management
- PWA widget page + manifest shortcuts
- Group schedule endpoint (timezones + locations)
- UI #3-#6: compact headers on tasks/calendar/projects/goals
- UI #9: mobile responsive top bars
- webauthn_credentials table

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/tasks/lib/api.ts

@@ -135,6 +135,19 @@ export interface Task {
   group_icon: string | null;
 }
 
+export interface GroupTimeZone {
+  days: number[];
+  from: string;
+  to: string;
+}
+
+export interface GroupLocation {
+  name: string;
+  lat: number | null;
+  lng: number | null;
+  radius_m: number;
+}
+
 export interface Group {
   id: string;
   name: string;
@@ -142,6 +155,8 @@ export interface Group {
   icon: string | null;
   sort_order: number;
   display_name?: string;
+  time_zones: GroupTimeZone[];
+  locations: GroupLocation[];
 }
 
 export interface Connector {