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/strategies/strategy_factory.py

@@ -0,0 +1,171 @@
+"""
+Strategy factory for creating subject-specific formatting strategies.
+
+This module provides centralized strategy creation with auto-detection
+support for determining the most appropriate strategy based on content.
+"""
+
+from typing import Union, List
+from ..core.interfaces import Strategy
+from .math_strategy import MathStrategy
+from .chemistry_strategy import ChemistryStrategy
+from .physics_strategy import PhysicsStrategy
+from .statistics_strategy import StatisticsStrategy
+
+
+class StrategyFactory:
+    """
+    Factory for creating subject-specific conversion strategies.
+
+    This factory provides centralized strategy creation with support for:
+    - Explicit strategy selection (math, chemistry, physics, statistics)
+    - Auto-detection based on equation content
+    - Fallback to math strategy as default
+    """
+
+    # Singleton instances for strategy reuse
+    _math_strategy: Union[MathStrategy, None] = None
+    _chemistry_strategy: Union[ChemistryStrategy, None] = None
+    _physics_strategy: Union[PhysicsStrategy, None] = None
+    _statistics_strategy: Union[StatisticsStrategy, None] = None
+
+    @classmethod
+    def create_strategy(cls, subject_mode: str = "math") -> Strategy:
+        """
+        Create a formatting strategy for the specified subject mode.
+
+        Args:
+            subject_mode: The subject area for formatting
+                         ("math", "chemistry", "physics", "statistics", or "auto")
+
+        Returns:
+            Strategy instance for the specified subject mode
+
+        Examples:
+            >>> factory = StrategyFactory()
+            >>> strategy = factory.create_strategy("chemistry")
+            >>> isinstance(strategy, ChemistryStrategy)
+            True
+
+            >>> strategy = factory.create_strategy("math")
+            >>> isinstance(strategy, MathStrategy)
+            True
+
+            >>> strategy = factory.create_strategy("invalid")
+            >>> isinstance(strategy, MathStrategy)  # Falls back to math
+            True
+        """
+        subject_mode = subject_mode.lower()
+
+        if subject_mode == "chemistry":
+            if cls._chemistry_strategy is None:
+                cls._chemistry_strategy = ChemistryStrategy()
+            return cls._chemistry_strategy
+
+        elif subject_mode == "physics":
+            if cls._physics_strategy is None:
+                cls._physics_strategy = PhysicsStrategy()
+            return cls._physics_strategy
+
+        elif subject_mode == "statistics":
+            if cls._statistics_strategy is None:
+                cls._statistics_strategy = StatisticsStrategy()
+            return cls._statistics_strategy
+
+        elif subject_mode == "auto":
+            # Auto-detection handled by auto_detect_strategy()
+            # For now, return math as default (will be enhanced later)
+            if cls._math_strategy is None:
+                cls._math_strategy = MathStrategy()
+            return cls._math_strategy
+
+        else:  # Default: "math" or any unrecognized mode
+            if cls._math_strategy is None:
+                cls._math_strategy = MathStrategy()
+            return cls._math_strategy
+
+    @classmethod
+    def auto_detect_strategy(cls, equation_text: str) -> Strategy:
+        """
+        Auto-detect the most appropriate strategy based on equation content.
+
+        Args:
+            equation_text: The equation text to analyze
+
+        Returns:
+            Strategy instance best suited for the content
+
+        Detection priority:
+            1. Chemistry (chemical elements, reaction arrows)
+            2. Physics (SI units, physical constants)
+            3. Statistics (statistical operators, distributions)
+            4. Math (default fallback)
+
+        Examples:
+            >>> factory = StrategyFactory()
+            >>> strategy = factory.auto_detect_strategy("Fe + H2SO4 → FeSO4 + H2")
+            >>> isinstance(strategy, ChemistryStrategy)
+            True
+
+            >>> strategy = factory.auto_detect_strategy("F = ma, where a = 9.8 m/s²")
+            >>> isinstance(strategy, PhysicsStrategy)
+            True
+
+            >>> strategy = factory.auto_detect_strategy("X ~ Normal(μ, σ²)")
+            >>> isinstance(strategy, StatisticsStrategy)
+            True
+
+            >>> strategy = factory.auto_detect_strategy("sin(x) + cos(x)")
+            >>> isinstance(strategy, MathStrategy)
+            True
+        """
+        # Create strategy instances if not already created
+        if cls._chemistry_strategy is None:
+            cls._chemistry_strategy = ChemistryStrategy()
+        if cls._physics_strategy is None:
+            cls._physics_strategy = PhysicsStrategy()
+        if cls._statistics_strategy is None:
+            cls._statistics_strategy = StatisticsStrategy()
+        if cls._math_strategy is None:
+            cls._math_strategy = MathStrategy()
+
+        # Priority order: Chemistry > Physics > Statistics > Math
+        # (Chemistry has most specific indicators)
+
+        if cls._chemistry_strategy.detect_context(equation_text):
+            return cls._chemistry_strategy
+
+        if cls._physics_strategy.detect_context(equation_text):
+            return cls._physics_strategy
+
+        if cls._statistics_strategy.detect_context(equation_text):
+            return cls._statistics_strategy
+
+        # Default: math strategy
+        return cls._math_strategy
+
+    @classmethod
+    def reset_cache(cls):
+        """
+        Reset the cached strategy instances.
+
+        This is useful for testing or when strategy implementations change.
+        """
+        cls._math_strategy = None
+        cls._chemistry_strategy = None
+        cls._physics_strategy = None
+        cls._statistics_strategy = None
+
+    @classmethod
+    def get_available_strategies(cls) -> List[str]:
+        """
+        Get list of available strategy names.
+
+        Returns:
+            List of strategy names that can be used with create_strategy()
+        """
+        return ["math", "chemistry", "physics", "statistics", "auto"]
+
+    def __repr__(self) -> str:
+        """String representation for debugging."""
+        return "StrategyFactory(math, chemistry, physics, statistics, auto)"