- Replace client HomeworkFilters component with server-side <form method="GET">
- Switch search param from `search` to `q`, add lesson title to search scope
- Change status filter from DB status field to feedback-count logic (pending=no feedbacks, reviewed=has feedbacks)
- Update pagination label to "Страница X из Y · Всего: N"
- Preserve all existing submission links and layout
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>