fix: account for KV limitations on expiration time

[Envek]

At KV docs Expiring keys section it is said that

Expiration targets that are less than 60 seconds into the future are not supported.

So using period of 10 seconds may result in surprising behavior (not sure what exactly will happen: either it will implicitly become 60 seconds or won't get expired at all?)

To work around that let's always set expiration to at least 60 seconds and check that reset in the stored data isn't in the past.