Upgrade to Zod 4

[a613]

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✅

Is your feature request related to a problem? Please describe.

The ADK currently uses zod 3.25.76, but there is a new major version 4 (latest is 4.2.1 as of Dec 15 2025).

Installing zod 4 causes type conflicts.

Describe the solution you'd like

Please use v4 of zod.

Describe alternatives you've considered

It is possible to use zod v3 for now.

Additional context

N/A

[Alfredoeb9]

Hello, can i take this issue on?

[cornellgit]

zod4 is a good idea. Please feel free to update it.

[kalenkevich]

Hello, thanks for the issue!

It would be really nice to support zod v3 (it has big adoption already) and v4 at the same time.