libxml-rs 0.1.0-alpha.11

Phase 9: EXSLT + xsltproc. Native-Rust forensic reimplementation of libxml2+libxslt with C ABI drop-in replacement. Complete EXSLT (exsl:node-set on RTFs, math, sets, strings, dynamic, dates, functions), full xsltproc CLI with upstream exit codes, byte-identical differential parity against libxslt 1.1.45 across a 12-case corpus, 1110 tests passing, XSLT 1.0 engine + all prior surfaces.
Documentation
/**
 * @file
 *
 * DTD validation API for libxml-rs
 *
 * Stub header — functions will be implemented in future phases.
 */

#ifndef __XML_VALID_H__
#define __XML_VALID_H__

#include <libxml/xmlversion.h>

#ifdef __cplusplus
extern "C" {
#endif

/* Functions will be declared here as they are implemented. */

#ifdef __cplusplus
}
#endif

#endif /* __XML_VALID_H__ */