feat: add per-patient Local folder in Documents page backed by Cloud Storage

- Documents page shows a "Local Folder" card for each selected patient
  with an "Open in Cloud Storage" button that deep-links to their folder
- Cloud Storage page reads ?folderId URL param on mount and auto-opens
  the folder panel for seamless navigation from Documents
- Backend: GET /api/cloud-storage/patient-folder/:patientId endpoint
  that idempotently gets or creates a top-level CloudFolder per patient
- CloudFolder schema gains optional patientId field linked to Patient
- Disk directories for cloud storage folders now use the folder's name
  (e.g. "Xiaohui Wang/") instead of the opaque "folder-{id}/" path

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

packages/db/generated/prisma/schema.prisma

@@ -78,6 +78,7 @@ model Patient {
   communications    Communication[]
   documents         PatientDocument[]
   conversation      PatientConversation?
+  cloudFolders      CloudFolder[]          @relation("PatientCloudFolder")
 
   @@index([insuranceId])
   @@index([createdAt])
@@ -479,15 +480,18 @@ model CloudFolder {
   userId    Int
   name      String
   parentId  Int?
+  patientId Int?
   parent    CloudFolder?  @relation("FolderChildren", fields: [parentId], references: [id], onDelete: Cascade)
   children  CloudFolder[] @relation("FolderChildren")
   user      User          @relation(fields: [userId], references: [id])
+  patient   Patient?      @relation("PatientCloudFolder", fields: [patientId], references: [id], onDelete: SetNull)
   files     CloudFile[]
   createdAt DateTime      @default(now())
   updatedAt DateTime      @updatedAt
 
   @@unique([userId, parentId, name]) // prevents sibling folder name duplicates
   @@index([parentId])
+  @@index([patientId])
 }
 
 model CloudFile {
@@ -602,11 +606,11 @@ model AiSettings {
   apiKey            String
   aiEnabled         Boolean @default(true)
   openAiKey         String  @default("")
-  openAiEnabled     Boolean @default(true)
+  openAiEnabled     Boolean @default(false)
   claudeAiKey       String  @default("")
-  claudeAiEnabled   Boolean @default(true)
+  claudeAiEnabled   Boolean @default(false)
   dentalMgmtKey     String  @default("")
-  dentalMgmtEnabled Boolean @default(true)
+  dentalMgmtEnabled Boolean @default(false)
   afterHoursEnabled Boolean @default(true)
   openPhoneReply    Boolean @default(false)