feat!: remove @prisma/client dependency, add generic client type C

- Add library-owned JSON/QueueJobRecord types replacing Prisma.InputJsonValue
- Add TransactionClient<C> replacing PrismaLightClient
- PrismaQueue/createQueue gain third type param C (inferred from prisma option)
- Internal delegate access via (this.#prisma as any)[delegateKey]
- Prisma.DbNull replaced with null through any-casted delegate
- JobResult now accepts void for workers that don't return a value
- isLocked() handles Prisma 7 adapter 55P03 in message fallback
- Remove src/utils/prisma.ts (DMMF table name detection removed)
- tableName defaults to "queue_jobs"