Make it clearer which tokens are managed by latr

[wbh1]

When looking at your tokens in the Linode API, it's not readily apparent which ones are managed by latr. We should consider automatically modifying the token names to something like latr:<token_label> to make it clearer.

[cxdy]

https://github.com/wbh1/latr/blob/main/internal/linode/client.go#L93

this is true (confirmed on my account)

maybe if the tokens are managed by latr we should give them unique labels too? i feel like this could get messy.