fix highlight Commits nav item on individual commit pages

The commit detail view was passing ~active:Summary to render_page, causing the Summary button to appear highlighted. Changed to ~active:Commits since viewing a commit belongs to that section.

Commit
de3367bb91b1614572fffd3e913c1ba7070d75ab
Author
Claude Sonnet 4 <claude@anthropic.invalid>
Author date
Committer
Marius Peter <dev@marius-peter.com>
Committer date
lib/views/repo.ml
index 38bc0399..c1002f6f 100644..100644
@@ -851,7 +851,7 @@
851 851 in
852 852 render_page
853 853 ~heading:(context.repo ^ " : " ^ Resolvers.short_hash commit.hash)
854 Removed: context ~active:Summary content
854 Added: context ~active:Commits content
855 855
856 856 let branches context branches =
857 857 let content =