What is the seed in Bonfida Token vesting?

i dont understand the “seed” part that i have to supply in init,create instruction

The seed is used to create the public key of the vesting account https://github.com/Bonfida/token-vesting/blob/master/program/src/processor.rs#L44 that is a program derived address.

If you are a dev you will find the best answer of what a program derived address is in the Solana documentation here Calling Between Programs | Solana Docs there is also a nice explanation on StackOverflow What is the seeds in creating account or finding the account in solana, and could the seeds be anything or be specific? - Stack Overflow

If you are not a dev and just want to use the vesting program to lock tokens, just pass a random buffer when creating the vesting account, for instance you can use https://github.com/Bonfida/token-vesting/blob/master/js/src/utils.ts#L125

thankyou for insight

btw, id like to report a bug in bonfida token vesting js version,
should i report it here?

Yes, you can also open a PR on github if you prefer