feat(swift): implement agenda planning module (Epic 4 UI)

- Add AgendaBlock core component with list, create, cancel, reschedule modes
- Implement AgendaListView with patient/type/location details and actions
- Implement AgendaCreateForm with fuzzy patient search and validation
- Implement AgendaCancelView with disambiguation support
- Implement AgendaRescheduleForm with date/time picker
- Integrate with server actions (create, cancel, reschedule)
- Add radio-group UI component
- Update documentation and status

components/swift/artifacts/blocks/agenda-block.tsx

@@ -0,0 +1,66 @@
+'use client';
+import React from 'react';
+import { Encounter, AppointmentTypeCode, LocationClassCode, CalendarEvent } from '@/app/epd/agenda/types';
+import { AgendaListView } from './agenda-list-view';
+import { AgendaCreateForm } from './agenda-create-form';
+import { AgendaCancelView } from './agenda-cancel-view';
+import { AgendaRescheduleForm } from './agenda-reschedule-form';
+
+export interface AgendaBlockProps {
+    mode: 'list' | 'create' | 'cancel' | 'reschedule';
+    appointments?: CalendarEvent[];
+    dateRange?: { start: Date; end: Date; label: string };
+    prefillData?: {
+        patient?: { id: string; name: string };
+        datetime?: { date: Date; time: string };
+        type?: AppointmentTypeCode;
+        location?: LocationClassCode;
+        notes?: string;
+    };
+    disambiguationOptions?: CalendarEvent[];
+    onClose?: () => void;
+}
+
+export function AgendaBlock({
+    mode,
+    appointments,
+    dateRange,
+    prefillData,
+    disambiguationOptions,
+    onClose,
+}: AgendaBlockProps) {
+    const renderContent = () => {
+        switch (mode) {
+            case 'list':
+                return (
+                    <AgendaListView
+                        appointments={appointments}
+                        dateRange={dateRange}
+                        onClose={onClose}
+                        onCancelAppointment={(evt) => console.log('Cancel requested', evt)}
+                        onViewDetails={(evt) => window.location.href = `/epd/agenda?focus=${evt.id}`}
+                    />
+                );
+            case 'create':
+                return <AgendaCreateForm prefillData={prefillData} onClose={onClose} />;
+            case 'cancel':
+                return (
+                    <AgendaCancelView
+                        disambiguationOptions={disambiguationOptions}
+                        prefillData={prefillData}
+                        onClose={onClose}
+                    />
+                );
+            case 'reschedule':
+                return <AgendaRescheduleForm prefillData={prefillData} onClose={onClose} />;
+            default:
+                return <div className="p-4 text-red-500">Unknown mode: {mode}</div>;
+        }
+    };
+
+    return (
+        <div className="w-full max-w-[600px] max-h-[80vh] overflow-y-auto bg-white border rounded shadow-sm">
+            {renderContent()}
+        </div>
+    );
+}