Refactor (DRY) workspace TTL/Schedule validation logic

[johnstcn]

What

We currently duplicate some validations of workspace TTL / autostart schedule. We should refactor these and put them all in one place.

Interesting to do it in the cli. Can we somehow put the validation on a datastructure and reuse it for the backend + frontend? Like reuse the same code?

Originally posted by @Emyrk in #2018 (comment)

Why

Don't make me Repeat mYself.

[ketang]

Validation is complicated. I like to do it as close to the user as possible. To avoid repeating yourself typically means your validation is against rules sent from the server to the client, which works for many though not all cases (e.g. valid IDs or very complex data). I mention this because I'd like to make it possible to avoid at least some of the server round trips during data entry.

[Emyrk]

The current validation was just the TTL duration to be within some constants iirc.

[johnstcn]

Right, and with the current "all-in-one" approach we can just have the validation be a shared library. However, this means it's more important for folks to have a matching CLI <-> server version.

[ketang]

Yeah I've done the shared library thing and would prefer to skip it altogether. It's a dead end.

[bpmct]

Gonna close this for now