fix(runtime): values() in scalar context returns count, not last element

[fglock]

Summary

Fix values() losing its scalar-context count when the result passes through a sub return (or any list-collapse path).

In real Perl, scalar(values %hash) returns the number of values, just like scalar(keys %hash). PerlOnJava already did this for direct calls, but as soon as the result went through a sub return the scalar context degraded to "last list element" semantics:

my %h = (a=>10, b=>20, c=>30);
sub f { return values %h }
my $x = f();   # Before: 30   |   After: 3

Root cause

RuntimeHash.keys() set scalarContextSize on the returned RuntimeArray so the later list-to-scalar conversion yielded the count. RuntimeHash.values() and RuntimeArray.values() did not, so any list-collapse path (sub return, comma operator, etc.) treated the result as a plain list and applied last-element semantics.

Fix

• RuntimeHash.values() sets scalarContextSize on the returned array for both the regular and TIED_HASH paths.
• RuntimeArray.values() now returns a fresh RuntimeArray aliasing the elements (so for (values @a) { $_++ } still mutates @a) with scalarContextSize set on the new array, so the original @a's own scalar-context behaviour is not affected.

How this surfaced

Class::MOP::Class::get_all_attributes ends in return values %attrs. Every scalar $meta->get_all_attributes therefore returned a stringified Moose::Meta::Attribute=HASH(0x…) instead of a count, breaking 3 subtests in MooseX::Role::Parameterized's t/001-parameters.t (and any downstream code using the same pattern).

Test plan

• make passes (full unit test suite)
• prove src/test/resources/unit shows identical pass/fail set vs master (no regressions; same pre-existing failures only)
• Direct scalar(values %h) still returns count
• return values %h from a sub returns count in scalar context
• for (values @a) { $_ *= 10 } still mutates @a (alias semantics preserved)
• for (values %h) { $_ *= 10 } still mutates hash values
• Targeted repro:

  $ ./jperl -e 'sub f{return values %{{a=>10,b=>20,c=>30}}} print scalar(f()),"\n"'
  3
  

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[fglock]

Superseded — commit moved to PR #618 (fix/walker-gate-property-based)