go/aead: Enforce 32-bit bounds checking for AESGCMSIV input.
go/aead: Enforce 32-bit bounds checking for AESGCMSIV input.

This aligns with the AEAD documentation in:
https://github.com/google/tink/blob/master/docs/PRIMITIVES.md

PiperOrigin-RevId: 348544404

google/tink,google/tink,google/tink,google/tink,google/tink,google/tink,google/tink,google/tink