init: WordFileParse docx→HTML 解析服务（含 Word EQ 域公式修复）

服务：Spring Boot 3.2 + docx4j 8.3.9，POST /api/v3/server_office_file/file/parse
      接受 .docx，返回 HTML（公式 → LaTeX，图片 → RustFS 外链）

公式支持三类来源：
- OMML（Word 2007+ 公式）      → Python omml_mathml2latex
- MathType OLE 对象            → Ruby mathtype2mathml → MathML → LaTeX
- Word EQ 域（老教辅主力）      → EqToLatexUtil（本次新增）

本次改动：
1. 新增 java-svc/.../core/EqToLatexUtil.java：
   移植自 jby backend-services office-core，EQ 语法 → LaTeX
   （\f→\dfrac、\r→\sqrt、\i→\int/\sum/\prod、\s→^{}/_{}、\b→\left\right、
     \a→array、\x→\boxed/\overline、\o\al 堆叠、圈码、化学符号、极限、连等式）
   品牌标记 JBYU* → WPU*，与采集端一致
2. CtoMathFinder：接上 EQ 分支（原为 not-ported 桩），域代码经
   EqToLatexUtil.convert 转 LaTeX 写入 eqLatexMap（WPEQNUM 占位符）
3. WordParseUtil.dealPlaceholder：EQ 的 LaTeX 同样加 \( \) 包裹
   （原先因 WPEQNUM 例外不加包裹，前端/MathJax 不渲染）

修前症状：教辅 Word 里分式/方程组/上下标整段丢失（如 {−1/3, 1} 变成 {－，1}）
修后实测：46 份教辅 2908 处 EQ 域全部还原，公式总数 2954 处、零未包裹残留

安全：application.yml（含 RustFS 密钥）不入库，提供 application.yml.example；
      OssService 的 @Value 默认密钥已清空

scripts/omml_mathml2latex/parsers/docx_parser.py

@@ -0,0 +1,143 @@
+"""
+DOCX parser for Microsoft Word documents.
+
+This parser handles .docx files, extracting OMML equations and converting
+them to MathML format using the existing DOCX processing pipeline.
+"""
+
+import os
+from typing import List
+from ..core.interfaces import Parser
+
+
+class DocxParser(Parser):
+    """
+    Parser for Microsoft Word .docx files.
+
+    This parser handles .docx files by extracting OMML equations and
+    converting them to MathML using the existing DOCX processing pipeline.
+
+    Examples:
+        Parse DOCX file:
+            >>> parser = DocxParser()
+            >>> results = parser.parse("equations.docx")
+            >>> isinstance(results, list)
+            True
+    """
+
+    def __init__(self):
+        """Initialize the DOCX parser."""
+        pass
+
+    def parse(self, source: str) -> List[str]:
+        """
+        Parse DOCX file and return list of MathML equation strings.
+
+        Args:
+            source: Path to .docx file
+
+        Returns:
+            List of MathML equation strings (extracted from DOCX)
+
+        Raises:
+            FileNotFoundError: If DOCX file doesn't exist
+            ValueError: If file is not a valid .docx file
+            RuntimeError: If DOCX processing fails
+
+        Examples:
+            >>> parser = DocxParser()
+            >>> # Assuming test.docx exists with equations
+            >>> results = parser.parse("test.docx")
+            >>> all(isinstance(eq, str) for eq in results)
+            True
+        """
+        # Validate file exists
+        if not os.path.exists(source):
+            raise FileNotFoundError(f"DOCX file not found: {source}")
+
+        # Validate file extension
+        if not source.lower().endswith('.docx'):
+            raise ValueError(f"File must have .docx extension: {source}")
+
+        # Import here to avoid circular dependencies
+        from ..processing import OMMLExtractor
+        from ..core import omml_to_mathml
+        from ..utils.styling_postprocessor import apply_styling_to_mathml_from_omml
+
+        # Get XSL path (in core module)
+        current_dir = os.path.dirname(os.path.abspath(__file__))
+        core_dir = os.path.join(os.path.dirname(current_dir), 'core')
+        xsl_path = os.path.join(core_dir, 'OMML2MML.xsl')
+
+        try:
+            # Extract OMML from DOCX using OMMLExtractor
+            extractor = OMMLExtractor()
+            equation_dicts = extractor.extract_from_docx(source)
+
+            if not equation_dicts:
+                # No equations found
+                return []
+
+            # Convert each OMML to MathML
+            results = []
+            for eq_dict in equation_dicts:
+                try:
+                    # Extract the cleaned OMML string from the dictionary
+                    omml_str = eq_dict.get('cleaned_omml', eq_dict.get('omml', ''))
+                    if not omml_str:
+                        continue
+
+                    # Step 1: XSLT transformation
+                    mathml_str = omml_to_mathml(omml_str, xsl_path)
+
+                    # Step 2: Post-process to fix table structure and add styling
+                    # CRITICAL: This fixes the OMML2MML.xsl bug where <mtr><mrow> should be <mtr><mtd>
+                    mathml_str = apply_styling_to_mathml_from_omml(omml_str, mathml_str)
+
+                    if mathml_str and mathml_str.strip():
+                        results.append(mathml_str)
+                except Exception as e:
+                    # Log error but continue with other equations
+                    print(f"Warning: Failed to convert OMML equation: {e}")
+                    continue
+
+            return results
+
+        except Exception as e:
+            raise RuntimeError(f"DOCX processing failed: {e}")
+
+    def can_handle(self, source: str) -> bool:
+        """
+        Check if this parser can handle the given input source.
+
+        Args:
+            source: Input source to check
+
+        Returns:
+            True if source is a .docx file, False otherwise
+
+        Examples:
+            >>> parser = DocxParser()
+            >>> parser.can_handle("equations.docx")
+            True
+            >>> parser.can_handle("<math><mi>x</mi></math>")
+            False
+        """
+        # Check file extension
+        if source.lower().endswith('.docx'):
+            return True
+
+        # Check if it's an existing file with .docx extension
+        if os.path.exists(source) and source.lower().endswith('.docx'):
+            return True
+
+        return False
+
+    @property
+    def parser_type(self) -> str:
+        """Get the parser type identifier."""
+        return "docx"
+
+    def __repr__(self) -> str:
+        """String representation for debugging."""
+        return "DocxParser()"