[perl #126241] operator names need to be valid, parsable Perl

nqp fix in a79e4abbe60d28f59b451416e7946ee433db7199 rakudo fix in 091637fd5ace48a0835fc8af786f2caa372381cf roast fix in dc3e1335232bb617b42d335ddbcc42be0a9dedaa

[perl #126284] --> Int:D allowed but not checked correctly

Marked existing tests as related to this ticket: https://github.com/perl6/roast/commit/5bd83c5b01 Closing ticket.

[perl #126284] --> Int:D allowed but not checked correctly

Seems to work now that we have DefiniteHOW: m: sub a() returns Int:U { 42 }; say &a.returns; a rakudo-moar 8f4e90: OUTPUT«(Int:U)␤Type check failed for return value; expected Int:U but got Int␤ in sub a at /tmp/LRo5pcMZof:1␤ in block at /tmp/LRo5pcMZof:1␤␤» m: sub a() returns Int:D { Int };