fix(menu): "N more on tangled.org…" opens one PR, not the repo's pull list #37

In a repo group with more than MAX_PER_GROUP (25) waiting PRs, the last row reads "N more on tangled.org…", but clicking it opens the newest PR in that repo instead of the repo's pull list.

Evidence. extension/extension.js:1014-1015 on main:

if (sorted.length > MAX_PER_GROUP)
    sub.menu.addAction(`${sorted.length - MAX_PER_GROUP} more on tangled.org…`, () => openUri(sorted[0].url));

sorted[0] is the first PR already listed above the row (best verdict first), so from the menu the hidden PRs can't be reached. Search only finds them if you already know a title: GNOME shows 5 results per provider (in the many-prs.json headless run, searching "tangled conflicted" shows 5 of the 10 conflicted PRs).

Proposal. Open the repo's pull list, https://tangled.org/<repoDid>/pulls (tangled.org redirects a repo DID the same way it does for pullUrl). The item's url minus its last two path segments gives that, and once #34 lands its new repoDid field does too. Optionally, a fixture repo with 26+ waiting PRs lets the headless run render the row.

Done when the row opens the repo's pull list, and a test or a headless shot covers a group with more than 25 PRs.