[Feature]: Support display mnemonic discreetly for keys mnemonic

[Halimao]

Summary

Ref #18662 #18668

simd keys mnemonic will also show mnemonic in output, we can show it discreetly on an alternate screen.

Problem Definition

As simd keys mnemonic will show the mnemonic, it would be more safe if we display mnemonic on an alternate screen

Proposed Feature

After we run simd keys mnemonic, the mnemonic will show on an alternate screen, with some prompt msg. With 'Enter' key press, will bring user back to original screen.

if user provide --indiscreet flag, will show on current terminal directly.

[Halimao]

I will draft a pr for this issue