Support `zod/v4` in `@farfetched/zod`

[kireevmp]

Since Zod v4 has been released in May, can we please add support for zod/v4 in zodContract?

The best option for the time being would be to expose both v3 and v4 import paths just like Zod does, to allow people to migrate.
This would require the minimum peer dependency to be bumped to ^3.25.0 from current ^3.19.0.

References:

• Zod v4 announcement: https://zod.dev/v4
• zod/v3 vs. zod/v4 versioning: Versioning with subpaths ("zod/v4") to enable incremental migration colinhacks/zod#4371

[termorey]

Created an implementation #544