trim PR title when too large for terminal in `gm gh pr checkout`

[amtoine]

input list has trouble

• scrolling when one line is too large
• treating ANSI sequences (they match, e.g the m in \0[m)

this PR computes custom lines that are trimmed to the size of the terminal and don't use ANSI coloring :thinking:

test it

• run

  tk run --interactive --sugar ["github"]

• go to a directory with remote PR, e.g. nushell/nushell
• run

  gm gh pr checkout