feat: zero-knowledge encryption Phase 1 — server can no longer read user data

Complete the core zero-knowledge property: all user data (medications,
appointments, profile names) is now client-encrypted via AES-GCM; the server
stores and returns opaque ciphertext and can never decrypt it.

Frontend crypto module (Web Crypto API, no deps):
- crypto/keys.ts: double-PBKDF2 derivation from the password — an auth secret
  (base64, sent to the server as the 'password') and an encryption key (AES-GCM
  CryptoKey, kept in memory only, never transmitted). In-memory key store.
- crypto/cipher.ts: AES-GCM encrypt/decrypt + JSON convenience wrappers.

Auth split: login/register now derive the auth secret + enc key from the
password BEFORE the API call. Only the auth secret (not the raw password) is
sent to the server. The server's PBKDF2 stays as-is (it hashes whatever it
receives) but can never derive the enc key.

Backend — server treats all data blobs as opaque:
- Medication: removed MedicationData + flat MedicationResponse; new
  MedicationResponse echoes metadata + encrypted_data blob. Create/update
  accept opaque blobs (whole-blob replace). MedicationData struct deleted.
- Appointment: same opaque treatment; status moved to a top-level document field
  so it remains filterable without decryption. AppointmentData struct deleted.
- Profile: name is now an opaque encrypted blob (name_data/name_iv). Auto-created
  profile starts empty; client sets it.
- EncryptedFieldWire shared wire type across medication/appointment.

Frontend — decrypt-on-read, encrypt-on-write:
- Stores derive the enc key on login/register; decrypt wire responses into
  domain objects on load; encrypt domain data into blobs on create/update.
- API client returns wire types (opaque blobs); components consume decrypted
  domain data (mostly unchanged — the store does the crypto).
- Updated store tests for the ZK contract (derive a real key, mock wire responses).
- 20 frontend tests pass, build clean.

Backend: 21 tests pass (removed MedicationData/appointment-data deser tests;
opaque-blob echo tests added), clippy 0 warnings.

KNOWN LIMITATIONS (Phase 2): forgotten password = data loss (no recovery wrapping
yet). Page reload requires re-entering the password to re-derive the enc key
(in-memory only, by design). No data migration (no real data existed).

web/normogen-web/src/services/api.ts

@@ -17,8 +17,10 @@ import {
   DoseLog,
   LogDoseRequest,
   AdherenceStats,
-  Profile,
-  Appointment,
+  MedicationWireResponse,
+  AppointmentWireResponse,
+  ProfileWireResponse,
+  EncryptedFieldWire,
   CreateAppointmentRequest,
   UpdateAppointmentRequest,
 } from '../types/api';
@@ -213,47 +215,48 @@ class ApiService {
     return response.data;
   }
 
-  // ---- Profile (Phase 3c) ----
+  // ---- Profile (zero-knowledge: opaque encrypted name) ----
 
-  async getProfile(): Promise<Profile> {
-    const response = await this.client.get<Profile>('/profiles/me');
+  async getProfile(): Promise<ProfileWireResponse> {
+    const response = await this.client.get<ProfileWireResponse>('/profiles/me');
     return response.data;
   }
 
-  async updateProfileName(name: string): Promise<Profile> {
-    const response = await this.client.put<Profile>('/profiles/me', { name });
+  async updateProfileName(nameData: string, nameIv: string): Promise<ProfileWireResponse> {
+    const response = await this.client.put<ProfileWireResponse>('/profiles/me', {
+      name_data: nameData,
+      name_iv: nameIv,
+    });
     return response.data;
   }
 
-  // ---- Medications ----
+  // ---- Medications (zero-knowledge: opaque encrypted blobs) ----
 
-  async getMedications(): Promise<Medication[]> {
-    const response = await this.client.get<Medication[]>('/medications');
+  async getMedications(): Promise<MedicationWireResponse[]> {
+    const response = await this.client.get<MedicationWireResponse[]>('/medications');
     return response.data;
   }
 
-  async getMedication(id: string): Promise<Medication> {
-    const response = await this.client.get<Medication>(`/medications/${id}`);
+  async getMedication(id: string): Promise<MedicationWireResponse> {
+    const response = await this.client.get<MedicationWireResponse>(`/medications/${id}`);
     return response.data;
   }
 
-  async createMedication(data: CreateMedicationRequest): Promise<Medication> {
-    const response = await this.client.post<Medication>('/medications', data);
+  async createMedication(data: CreateMedicationRequest): Promise<MedicationWireResponse> {
+    const response = await this.client.post<MedicationWireResponse>('/medications', data);
     return response.data;
   }
 
-  async updateMedication(id: string, data: UpdateMedicationRequest): Promise<Medication> {
-    // Backend update is POST /:id (not PUT).
-    const response = await this.client.post<Medication>(`/medications/${id}`, data);
+  async updateMedication(id: string, data: UpdateMedicationRequest): Promise<MedicationWireResponse> {
+    const response = await this.client.post<MedicationWireResponse>(`/medications/${id}`, data);
     return response.data;
   }
 
   async deleteMedication(id: string): Promise<void> {
-    // Backend delete is POST /:id/delete (not DELETE /:id).
     await this.client.post(`/medications/${id}/delete`);
   }
 
-  // ---- Dose logging + adherence (Phase 3c) ----
+  // ---- Dose logging + adherence (not encrypted — counts/flags only) ----
 
   async logDose(medicationId: string, req: LogDoseRequest): Promise<DoseLog> {
     const response = await this.client.post<DoseLog>(`/medications/${medicationId}/log`, req);
@@ -265,27 +268,27 @@ class ApiService {
     return response.data;
   }
 
-  // ---- Appointments ----
+  // ---- Appointments (zero-knowledge: opaque encrypted blobs) ----
 
-  async getAppointments(status?: string): Promise<Appointment[]> {
-    const response = await this.client.get<Appointment[]>('/appointments', {
+  async getAppointments(status?: string): Promise<AppointmentWireResponse[]> {
+    const response = await this.client.get<AppointmentWireResponse[]>('/appointments', {
       params: status ? { status } : undefined,
     });
     return response.data;
   }
 
-  async getAppointment(id: string): Promise<Appointment> {
-    const response = await this.client.get<Appointment>(`/appointments/${id}`);
+  async getAppointment(id: string): Promise<AppointmentWireResponse> {
+    const response = await this.client.get<AppointmentWireResponse>(`/appointments/${id}`);
     return response.data;
   }
 
-  async createAppointment(data: CreateAppointmentRequest): Promise<Appointment> {
-    const response = await this.client.post<Appointment>('/appointments', data);
+  async createAppointment(data: CreateAppointmentRequest): Promise<AppointmentWireResponse> {
+    const response = await this.client.post<AppointmentWireResponse>('/appointments', data);
     return response.data;
   }
 
-  async updateAppointment(id: string, data: UpdateAppointmentRequest): Promise<Appointment> {
-    const response = await this.client.post<Appointment>(`/appointments/${id}`, data);
+  async updateAppointment(id: string, data: UpdateAppointmentRequest): Promise<AppointmentWireResponse> {
+    const response = await this.client.post<AppointmentWireResponse>(`/appointments/${id}`, data);
     return response.data;
   }