cli: color author and commiter names yellow

When `format_short_signature(signature)` is set to `signature.name()` the author names are not yellow like other signature types (eg email and username). When the commit signatures have no colors, they blend in making it hard to distinguish between signatures and commit messages.

If just `name` were set to `yellow`, just like email and username, it affects the colorization of branch names making them also yellow despite them being designated as magenta. Setting `author` and `committer` to `yellow` is specific enough to allow branches to keep their colors while still coloring signature names. This is known to affect signatures in both 'log' and 'show'.

CHANGELOG.md

@@ -36,6 +36,8 @@ to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
   (inherit from parent; default), `full` (full working copy), or `empty` (the
   empty working copy).
 
+* Color author and committer names yellow
+
 ### Fixed bugs
 
  * Fixed panic when parsing invalid conflict markers of a particular form.
@@ -69,7 +71,7 @@ to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 * A tilde (`~`) at the start of the path will now be expanded to the user's home
   directory when configuring a `signing.key` for SSH commit signing.
-  
+
 * When reconfiguring the author, warn that the working copy won't be updated
 
 ### Fixed bugs
@@ -169,7 +171,7 @@ Thanks to the people who made this release happen!
 
 * `jj backout` can now back out multiple commits at once.
 
-* `jj git clone some/nested/path` now creates the full directory tree for 
+* `jj git clone some/nested/path` now creates the full directory tree for
    nested destination paths if they don't exist.
 
 * String patterns now support case‐insensitive matching by suffixing any

cli/src/config/colors.toml

@@ -23,6 +23,8 @@
 
 "email" = "yellow"
 "username" = "yellow"
+"author" = "yellow"
+"committer" = "yellow"
 "timestamp" = "cyan"
 "working_copies" = "green"
 "branch" = "magenta"