Bond timestamps

When creating a bond, the creator provides the issuance timestamp as an argument to the instruction. This issuance argument could be any timestamp before the maturity timestamp, and not the true issuance time of the bond.

A user could create a bond with the issuance timestamp far in the past or far in the future, which changes the total timespan of the bond. This scales the amount of yield tokens minted for each deposit. However, this issue does not appear to be exploitable since this affects all users proportionally. But, this could still lead to potential confusion.

The issuance timestamp could instead be set from the Unix timestamp provided by the Clock sysvar rather than provided by the user, which would make it the true issuance time of the bond.