Types for "infinite" connection timer options

The connection timer options idle_timeout, max_lifetime, and connect_timeout support any falsy values for nullable timeouts via the timer() helper:

https://github.com/porsager/postgres/blob/e7dfa14519f363229ccc3ead7b1b2f2051937efb/src/connection.js#L1044-L1045

but the types are inconsistently declared as number or number | undefined then wrapped in Partial<> (effectively adding | undefined).

While it's true that using, e.g. connect_timeout: undefined would technically work with the current parseOptions use of k in o, it's potentially confusing with the defaulting logic when it's not present at all, so connect_timeout: 0 is currently the IMO best option to explicitly state you don't want a timeout, even if it's a bit weird looking.

It would be nice if other options like null or false were permitted, if this support is intentional? (Since this behavior isn't mentioned in the README that I could see)

Happy to PR if you think this is a good idea.

Start with src/connection.js around the timer() helper and parseOptions, then inspect the existing option type declarations for idle_timeout, max_lifetime, and connect_timeout. Determine whether null and false are intentionally supported; done means the declared types, runtime behavior, and any README explanation agree.