Per-chat CFG applies a CFG setting per-chat only rather than character
or globally. This overrides all other CFG settings (this will be changed).
Also add fixes to remove character CFG entries properly and not to
apply CFG if the scale is 1 as that won't do anything to generation.
Signed-off-by: kingbri <bdashore3@proton.me>
CFG is bundled as an extension which is more flexible in terms of
storing settings and consolidating code.
Global CFG is currently supported and the old power user setting
is auto-migrated.
Signed-off-by: kingbri <bdashore3@proton.me>