feat(web-ui): paginate and collapse tasks list

[LIU9293]

Summary

• Show the 10 most recent one-time tasks by default, with a Load more button that appends another 10 at a time.
• Collapse each task row by default; the message body, timestamps, and error block only render when a row is expanded.
• Count badge shows visible / total while the list is partially loaded.
• Bump root version to 0.1.34.

Notes

• Backend SQL ordering is unchanged (running → pending → others, then scheduled_at ASC / created_at DESC), so "most recent" already surfaces first.
• Editing a task auto-expands it and pulls it into the visible window if it was beyond the current page.