Make picker preview scrollable

[izzqz]

It would be great if the any picker allowed scrolling through preview contents, similar to implementations in other tui applications like yazi or lazygit

Helix could use the same hotkeys:
Shift + 🠅/PgUp - scroll preview up
Shift + 🠇/PgDn - scroll preview down

[nik-rev]

duplicate of #1614

there is a PR for this as well: #11441