IG5 JPype Unicode bootstrap modification

This directory retains JPype 1.5.2 upstream source, support JAR, LICENSE and
NOTICE. JPype is licensed under Apache-2.0; IG5's project license does not
replace or restrict the upstream license.

IG5 modifies only JPypeContext.createContext: when the IG5-specific
ig5.jpype.native_filename system property is set to the single permitted
_jpype.cp312-win_amd64.pyd filename, Java resolves that filename against its
Unicode user.dir before System.load. With the property absent, upstream
nativeLib handling remains unchanged. This is a modified upstream component,
not an unmodified JPype release or a change approved by the upstream project.

The original support JAR SHA-256 is
a8c993bccb81392102fca126d4d716605cbda2c6df2846d42c92dc3672bfd4f2.
The runtime manifest and licenses/ig5-jpype-bootstrap/provenance.json record
the modified JAR and source hashes. No system Python, Java or user installation
is modified. The complete original JAR is retained here as a reproducible
build input; only the runtime copy is replaced.
