refactor: cache handling and improve cache action logs

[penandlim]

Cache was not saving on some of my actions with cache input not explicitly set - moving the check of cache input into js seems to have fixed it.

• Refactor cache handling and improve cache action logs
• Use getBooleanInput to ensure boolean type
• Add helpful logging similar to actions/setup-* repos to see which cache was restored/saved.
• Add early exit on post-action for a workaround. With a 200kb cache, post-action time is decreased from 2min~ -> 2 seconds.

[onbjerg]

when does this happen? should we add a log?

[penandlim]

Looks like it happens when there is an existing cache with the primary key thus fails saving the cache.
It doesn't throw an error and prints a message like this before returning with -1.

Failed to save: Unable to reserve cache with key linux-foundry-chain-fork-c2ec5babbad85fecbae9c860472722f98f36c164, another job may be creating this cache. More details: Cache already exists. Scope: refs/heads/master, Key: linux-foundry-chain-fork-c2ec5babbad85fecbae9c860472722f98f36c164, Version: d8cfedd31e23b815ad861b2e68523a31664eaf28c2ddc7b682eb115646a473d9

[penandlim]

https://github.com/actions/toolkit/blob/415c42d27ca2a24f3801dd9406344aaea00b7866/packages/cache/src/cache.ts#L245-L246

[onbjerg]

thank you