## Problem
The `set` and `clear` subcommands don't clearly convey their intent —
`set`
reads like a generic setter rather than an auth action, and `clear`
overloads
single-platform and all-platform semantics in one subcommand.
## Solution
Rename `set` to `login`, split `clear` into `logout` (per-platform,
defaults
to active) and `clear` (all platforms).
New API:
- `:CP credentials login [platform]` — prompt and save credentials
- `:CP credentials logout [platform]` — remove credentials for one
platform
- `:CP credentials clear` — remove all stored credentials
98ac0aa7a7