Drop additions that the UX plan does not ask for:
- the interactive label edit form; label edit now requires a flag
- label clone and the skip mode of label creation it needed
- repo rename rewriting the Git remote or tea.repository; it now
warns that the remote still points to the old name
- the extra "source" remote on clones of pull mirrors
- run artifact download, which duplicates run download --zip
- 256-color and 24-bit label swatches; colors stay ANSI 16
- config list --show-source (config get keeps it)
- the membership and access GETs before team member/repo add and
remove; Gitea's PUT and DELETE are idempotent
label edit/delete keep --by-name: it is the only way to address a
label whose name is a number that is also another label's ID.
Signed-off-by: bircni <bircni@icloud.com>