feat(api): API improvements — pagination, bulk ops, comments, members, archival

[RainyPixel]

Summary

Addresses items from #1041 and adds additional API improvements:

• Pagination: GET /tasks/:projectId now returns { data, pagination } with total/page/pageSize/totalPages. Pagination only applied when page or limit params are passed (no breaking change for existing clients).
• Sorting: sortBy and sortOrder query params on task list (createdAt, priority, dueDate, position, title, number)
• Due date filtering: dueBefore and dueAfter query params with date validation
• Bulk operations: PATCH /task/bulk supporting updateStatus, updatePriority, updateAssignee, delete, addLabel, removeLabel
• Comments: Dedicated GET/POST/PUT/DELETE /comment endpoints with author-only edit/delete
• Workspace members: GET /workspace/:id/members returns name, email, image, role
• Project archival: PUT /project/:id/archive|unarchive with soft-delete, includeArchived filter

Test plan

• Fetch tasks without page/limit — verify all tasks returned (no truncation)
• Fetch tasks with ?page=1&limit=10 — verify pagination metadata
• Sort tasks by priority desc — verify ordering
• Filter by dueBefore/dueAfter — verify date range works
• Bulk update status for multiple tasks — verify all updated
• Create/edit/delete a comment — verify CRUD and author-only restrictions
• Get workspace members — verify member list returned
• Archive a project — verify it's hidden from default list
• Unarchive — verify it reappears