fix: remove old stale data

apps/api/prisma/schema.prisma

@@ -15,7 +15,6 @@ model Venue {
 
   devices          Device[]
   clientUsers      ClientUser[]
-  tabOwnerships    TabOwnership[]
   remoteCommands   RemoteCommand[]
   auditLogs        AuditLog[]
   regCodes         RegistrationCode[]
@@ -43,9 +42,7 @@ model Device {
   revokedAt      DateTime?
   createdAt      DateTime  @default(now())
 
-  venue          Venue             @relation(fields: [venueId], references: [id])
-  tabSnapshots   OpenTabSnapshot[]
-  tabOwnerships  TabOwnership[]
+  venue          Venue           @relation(fields: [venueId], references: [id])
   remoteCommands RemoteCommand[]
   tabEvents      TabEvent[]
   settlements    Settlement[]
@@ -81,38 +78,6 @@ model RegistrationCode {
   @@index([venueId])
 }
 
-model OpenTabSnapshot {
-  id           String   @id @default(uuid())
-  deviceId     String
-  tabId        String
-  customerName String
-  version      Int
-  totalInCents Int
-  itemCount    Int
-  // The tab's lines as reported by the terminal: [{ productName, quantity, unitPriceInCents }].
-  // Null for terminals running an app version that doesn't report them.
-  items        Json?
-  reportedAt   DateTime
-
-  device Device @relation(fields: [deviceId], references: [id])
-
-  @@unique([deviceId, tabId])
-  @@index([deviceId])
-  @@index([tabId, reportedAt])
-}
-
-model TabOwnership {
-  tabId          String
-  venueId        String
-  deviceId       String
-  lastReportedAt DateTime
-
-  venue  Venue  @relation(fields: [venueId], references: [id])
-  device Device @relation(fields: [deviceId], references: [id])
-
-  @@id([venueId, tabId])
-}
-
 // A request from the dashboard. close_tab used to be executed by the owning terminal; the server now settles
 // the tab itself and records the command as completed right away, for the history.
 model RemoteCommand {