failed to decode base64 string Rust backend

[jacksonwalters]

the Rust binary fails to decode a base64 string under certain circumstances when sending a message.

it appears that the actual error message itself becomes the encrypted string, which is then decrypted properly to the following:

[id=24] jackson --> jackson [2025-10-08 21:43:07 EST]: thread 'main' panicked at src/utils.rs:104:64: Failed to decode base64 string: InvalidByte(132, 46) note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

[jacksonwalters]

now we are catching the exception. it appears to be a Rust issue with certain strings. need to find failing cases.

[jacksonwalters]

now that the exception is caught, this could be moved to https://github.com/lattice-based-cryptography/module-lwe.