feat(02-01): Prisma schema expansion, RLS migration, and PrismaModule

- Add User, Role enum, PasswordResetToken, LdapConfig, LdapFieldMapping models
- Expand Tenant model with isActive, users relation, ldapConfig relation
- Create RLS migration with tenant isolation policies on all tenant-scoped tables
- Create PrismaModule (global), PrismaService, and forTenant extension
- Add JWT_SECRET, TESSERA_ADMIN_*, TESSERA_FORCE_CHANGE env vars to docker-compose
- Install @nestjs/jwt, @nestjs/passport, passport, argon2, class-validator deps

apps/api/src/prisma/prisma.service.ts

@@ -0,0 +1,9 @@
+import { Injectable, OnModuleInit } from '@nestjs/common';
+import { PrismaClient } from '@prisma/client';
+
+@Injectable()
+export class PrismaService extends PrismaClient implements OnModuleInit {
+  async onModuleInit() {
+    await this.$connect();
+  }
+}