[feature] Add EXPath Binary Module 4.0 as built-in extension module

[joewiz]

Summary

• Ports the EXPath Binary Module 4.0 (http://expath.org/ns/binary) from a standalone XAR package (eXist-db/exist-binary) to a built-in extension module
• Makes the module available out of the box — no XAR installation required
• Implements binary data manipulation: hex/bin/octal conversion, packing/unpacking, bitwise operations, text encoding/decoding

What Changed

New module: extensions/modules/expath-binary/

• 8 Java classes ported from eXist-db/exist-binary (40+ functions)
• Functions organized by category: conversions, basic operations, text encoding, numeric packing, bitwise operations
• Artifact ID: exist-expath-binary

Registration:

• extensions/modules/pom.xml — added expath-binary module
• exist-distribution/pom.xml — added exist-expath-binary runtime dependency
• exist-distribution/src/main/config/conf.xml — registered http://expath.org/ns/binary

XQTS Impact

The QT4 test suite contains 574 EXPath Binary tests across 27 bin-* test sets, plus 190 EXPath File tests in a companion PR (#6257) — 764 tests total that currently fail because these modules aren't available to the XQTS runner. Making them built-in extension modules resolves this. The standalone XAR achieved 96% compliance.

Spec References

• EXPath Binary Module 4.0

Test Plan

• exist-core XQSuite tests pass (no regressions)
• Module compiles and dependency analysis passes
• XQTS bin-* test sets (after merge to integration branch)

🤖 Generated with Claude Code

[reinhapa]

Please address previous comments

[joewiz]

[This response was co-authored with Claude Code. -Joe]

Thanks @reinhapa — addressed in b47f051:

• BinaryBasicFunctions: Replaced labeled continue outer with a boolean match flag to avoid branching statement as last in loop
• BinaryBitwiseFunctions: Converted bitwise operation switch to switch-as-expression
• BinaryModuleHelper: Converted octet order switch to switch-as-expression with merged case labels
• BinaryConversionFunctions: Reduced NPath complexity in octalToBinary by extracting stripAndValidateOctal, octalToBinaryString, and binaryStringToBytes helper methods
• BinaryTextFunctions: Reduced NPath complexity in decodeString by extracting validateOffsetAndSize, decodeBytes, getOptionalStringArg, and getOptionalIntArg helper methods