Ly, Length 20 / Score 4
Input cannot have 4 characters 0&o0`&o and ` (which I can't figure out how to highlight with the rest of them since it's the markdown character for starting and ending a highlighted string. :)
&ir[0u['`o,]p]"&o"&o
And at a high level, the code reads all input as codepoints, then converts each character to a 0 and as many "increment the top of stack" instructions as is necessary to get to the codepoint value. Then it appends &o to the end to print the entire stack as characters.
&ir - read input as codepoints, reverse stack
[ ] - loop once for each char on the stack
0u - push a "0" onto the stack
[ ] - while number is >0
'`o - print "`" (the increment instruction)
, - decrement the top of stack
p - delete the loop variable from the stack
"&o" - push "&o" (print whole stack instruction)
&o - print stack
