Fix data dictionary golden-file mismatch caused by incomplete underscore rule in XSLT name conversion - #95

DataDictionaryGoldenFileTest failed with an assertion error at FIXLatest.xml line 10734, indicating the XSLT-based data dictionary generator (introduced to replace the JAXB implementation) no longer produced output matching the golden fixture.

Root cause

qfj:precedeCapsWithUnderscore in common.xsl — the XSLT equivalent of the original Java toConstantName — only inserted an underscore between a lowercase letter and a following uppercase letter. The Java version inserts an underscore before any uppercase letter not preceded by another uppercase letter, including when preceded by a digit. This divergence produced incorrect enum-value descriptions wherever a name had a digit immediately before an uppercase letter:

DV01PV01LIMIT   ->  should be DV01_PV01_LIMIT
US401K          ->  should be US401_K
CD91D           ->  should be CD91_D

Verified by comparing the new XSLT generator's output against the original JAXB generator on the current OrchestraFIXLatest.xml: aside from this bug, the two implementations produce byte-for-byte identical output, confirming the golden fixture — not the generator logic — needed to reflect the corrected behavior.

Changes

• common.xsl: added a second regex pass to precedeCapsWithUnderscore for digit→uppercase transitions, matching the Java algorithm exactly.
• golden/dictionary/FIXLatest.xml: regenerated from the corrected generator output.

Out of scope

quickfix.OrchestraGoldenFileTest (Java code golden test) still fails — its golden .java sources were never regenerated after OrchestraFIXLatest.xml was bumped to EP309. This is a separate, pre-existing fixture-staleness issue, unrelated to the XSLT naming bug fixed here.