refactor(cortex): Epic 0 - Extract patient search hooks & components (E0.S1-S4)

DRY refactor: Extract reusable patient search logic from ZoekenBlock.

New files:
- lib/cortex/hooks/use-patient-search.ts (116 lines)
  Debounced patient search with abort controller
- lib/cortex/hooks/use-patient-selection.ts (98 lines)
  FHIR fetch + store update flow
- lib/fhir/patient-mapper.ts (109 lines)
  FHIR Patient to DB Patient mapping + utilities
- components/cortex/shared/patient-list-item.tsx (114 lines)
  Reusable patient list item with loading states

Refactored:
- ZoekenBlock: 349 -> 127 lines (-64%)

Documentation:
- docs/intent/patient-search/ux-analyse-patient-selectie.md
- docs/intent/patient-search/bouwplan-patient-selectie-v1.md

CLAUDE.md updated with Cortex architecture documentation.

Epic 0 complete: 4/4 stories (4 SP)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

lib/cortex/hooks/use-patient-selection.ts

@@ -0,0 +1,130 @@
+'use client';
+
+/**
+ * usePatientSelection Hook
+ *
+ * Handles patient selection flow: fetch FHIR data, map to DB format, update store.
+ * Extracted from ZoekenBlock for DRY compliance.
+ *
+ * Epic: E0.S4 (Patient Selectie - Refactor)
+ */
+
+import { useState, useCallback } from 'react';
+import { useToast } from '@/hooks/use-toast';
+import { useCortexStore } from '@/stores/cortex-store';
+import { safeFetch, getErrorInfo } from '@/lib/cortex/error-handler';
+import { mapFhirToDbPatient, type Patient } from '@/lib/fhir/patient-mapper';
+import type { PatientSearchResult } from './use-patient-search';
+
+interface UsePatientSelectionOptions {
+  /** Callback after successful selection */
+  onSuccess?: (patient: Patient, patientName: string) => void;
+  /** Callback on error */
+  onError?: (error: Error) => void;
+  /** Add to recent actions (default: true) */
+  trackRecentAction?: boolean;
+  /** Show toast on success (default: true) */
+  showSuccessToast?: boolean;
+}
+
+interface UsePatientSelectionReturn {
+  /** Select a patient by search result */
+  selectPatient: (patient: PatientSearchResult) => Promise<Patient | null>;
+  /** Whether a selection is in progress */
+  isSelecting: boolean;
+  /** ID of the patient currently being selected */
+  selectedId: string | null;
+  /** Clear selection state */
+  clearSelection: () => void;
+}
+
+export function usePatientSelection(
+  options: UsePatientSelectionOptions = {}
+): UsePatientSelectionReturn {
+  const {
+    onSuccess,
+    onError,
+    trackRecentAction = true,
+    showSuccessToast = true,
+  } = options;
+
+  const [isSelecting, setIsSelecting] = useState(false);
+  const [selectedId, setSelectedId] = useState<string | null>(null);
+  const { toast } = useToast();
+
+  const { setActivePatient, addRecentAction } = useCortexStore();
+
+  const selectPatient = useCallback(
+    async (patient: PatientSearchResult): Promise<Patient | null> => {
+      setIsSelecting(true);
+      setSelectedId(patient.id);
+
+      try {
+        // Fetch full FHIR patient data
+        const response = await safeFetch(
+          `/api/fhir/Patient/${patient.id}`,
+          undefined,
+          { operation: 'Patient data ophalen' }
+        );
+        const fhirPatient = await response.json();
+
+        // Map to DB format
+        const dbPatient = mapFhirToDbPatient(fhirPatient);
+
+        // Update store
+        setActivePatient(dbPatient);
+
+        // Track recent action
+        if (trackRecentAction) {
+          addRecentAction({
+            intent: 'zoeken',
+            label: `Patient geselecteerd: ${patient.name}`,
+            patientName: patient.name,
+          });
+        }
+
+        // Show success toast
+        if (showSuccessToast) {
+          toast({
+            title: 'Patient geselecteerd',
+            description: `${patient.name} is nu actief`,
+          });
+        }
+
+        // Call success callback
+        onSuccess?.(dbPatient, patient.name);
+
+        return dbPatient;
+      } catch (error) {
+        console.error('Failed to select patient:', error);
+
+        const errorInfo = getErrorInfo(error, { operation: 'Patient selecteren' });
+        toast({
+          variant: 'destructive',
+          title: errorInfo.title,
+          description: errorInfo.description,
+        });
+
+        onError?.(error instanceof Error ? error : new Error(String(error)));
+
+        return null;
+      } finally {
+        setIsSelecting(false);
+        setSelectedId(null);
+      }
+    },
+    [setActivePatient, addRecentAction, toast, trackRecentAction, showSuccessToast, onSuccess, onError]
+  );
+
+  const clearSelection = useCallback(() => {
+    setIsSelecting(false);
+    setSelectedId(null);
+  }, []);
+
+  return {
+    selectPatient,
+    isSelecting,
+    selectedId,
+    clearSelection,
+  };
+}