Fix Sub::Import detection of Sub::Exporter-based importers #1206

Summary

Sub::Import 1.002 fails its Sub::Exporter import test on both PerlOnJava execution backends, while the complete upstream test suite passes under system Perl.

Reproduction

• CPAN random run: 20260831-214225-16920
• Distribution: Sub::Import 1.002
• Failing test: t/import-se.t

The test imports foo from a test package configured with Sub::Exporter and expects it to be available as bar.

Results

• System Perl: 3/3 test programs pass.
• PerlOnJava JVM backend: t/import-se.t exits 255 before producing TAP.
• PerlOnJava interpreter backend: t/import-se.t exits 255 before producing TAP.

Observed behavior

PerlOnJava reports:

Sub::Import only handles Sub::Exporter and Exporter-based import methods

The failure comes from Sub::Import::_create_methods_fallback, meaning PerlOnJava does not recognize the SE test package as a Sub::Exporter-based importer. The same upstream test succeeds under system Perl.

This appears to be a PerlOnJava B/subroutine introspection or Sub::Exporter detection compatibility issue, rather than a Sub::Import module defect.