fix(git): parse co-author trailers that are not RFC 5322 addresses (#39076) (#39081)

Backport #39076 by @4RH1T3CT0R7

Bot co-authors like `dependabot[bot]` render as one long string with the
email inside the name, and never get truncated, so they overflow the
column.

Co-author idents are parsed with `net/mail`, but a git ident isn't an
email address. `mail.ParseAddress` rejects the whole value when the name
holds characters RFC 5322 reserves, like a `[bot]` suffix or a comma, so
the error branch keeps the raw trailer as the display name and throws
the address away. No address means no `mailto:` link, and the anchor is
what `.avatar-stack-names` truncates.

So parse the angle-addr ourselves when `net/mail` won't take it.
Splitting on the last `<` is safe because git strips angle brackets from
idents. The bare-name branch gets the class too.

Fixes https://github.com/go-gitea/gitea/issues/38949

Co-authored-by: Artem Lytkin <146867384+4RH1T3CT0R7@users.noreply.github.com>

modules/templates/util_render.go

@@ -415,7 +415,7 @@ func (ut *RenderUtils) participantNameLink(data *user_model.AvatarStackData, par
 	if participant.GitIdentity.Email != "" {
 		return htmlutil.HTMLFormat(`<a class="muted" href="mailto:%s">%s</a>`, participant.GitIdentity.Email, participant.GitIdentity.Name)
 	}
-	return template.HTML(template.HTMLEscapeString(participant.GitIdentity.Name))
+	return htmlutil.HTMLFormat(`<span class="avatar-stack-name">%s</span>`, participant.GitIdentity.Name)
 }
 
 func (ut *RenderUtils) participantPopupRow(data *user_model.AvatarStackData, participant *user_model.CommitParticipant) template.HTML {