You need chomp

#!/usr/bin/env perl
use strict;
use warnings;


my @files = `ls *ext`;
my $wanted = $files[0];
print $wanted;
print "Done$/$/$/"; # $/ = $INPUT_RECORD_SEPARATOR ie newline

chomp($wanted);

print $wanted;
print quotemeta($wanted);
print "Done";
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Output:

Weird File Name with Charactesr(1982){1996 Remaster}.ext
Done


Weird File Name with Charactesr(1982){1996 Remaster}.extWeird\ File\ N
+ame\ with\ Charactesr\(1982\)\{1996\ 
Remaster\}\.extDone
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You can even use in one line

chomp(my @files = `ls`);
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