Fix messy progress bar in dump_range

[roynalnaruto]

Closes #151

The PR fixes the messy progress bar display in terminal when witnesses for a range of blocks are being dumped.

• Uses MultiProgress and adds each ProgressBar to it
• Removes printlns
• Minor changes to the message
• Uses tokio::fs instead of std::fs for async writing to file

The progress bar now updates the message on the same line (for each tokio task) instead of moving to the next line.

Terminal output from this approach seems much more cleaner and clearer.

Demo

[lightsing]

could you also add .inspect(|e| dev_error!("{e}")) to L123 and L129 so we can see the actual error.

[lightsing]

let me take this pr from here. thx @roynalnaruto