docs: add CLAUDE.md with project architecture guidance

Add comprehensive documentation for Claude Code including:
- VBA module architecture and data flow
- Conditional logic syntax and parsing behavior
- Column mapping and header priority configuration
- Development commands for running converter and tests
- Git workflow and Claude Code integration

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

CLAUDE.md

@@ -0,0 +1,162 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+AutoBOM is an Excel-based Bill of Materials (BOM) management system for pressure product manufacturing. It uses VBA macros to parse conditional logic rules and generate categorized BOM configurations from Excel spreadsheets.
+
+## Architecture
+
+### Core VBA Modules (VBA/Modules/)
+
+The system follows a modular architecture with clear separation of concerns:
+
+- **M01_Main.bas** - Entry point and orchestration. Run `RunBOMConversion()` to execute the full workflow.
+- **M02_DataIO.bas** - Data input/output operations. Reads source data from "平台配置清单" worksheet and generates categorized output workbooks.
+- **M03_Logic.bas** - Core recursive parser for conditional expressions. Handles logical operators (AND/OR), nested parentheses, and key=value/key!=val conditions. Implements Cartesian products for set operations.
+- **M04_Config.bas** - Column mapping and header priorities. Defines source data columns (CODE, NAME, QTY, CONDITION, CATEGORY) and standard ordering for output.
+- **M99_TestRunner.bas** - Unit testing framework. Run `RunAllTests()` in VBA Immediate window to execute tests.
+
+### Class Module
+
+- **clsErrorLogger.cls** - Error handling and logging. Tracks conflicts, parsing failures, and provides detailed context without stopping execution.
+
+### Data Flow
+
+```
+Excel "平台配置清单" → M01_Main → M02_DataIO.LoadSourceData() →
+M03_Logic.ParseExpression() → Category Dictionary →
+M02_DataIO.CreateOutputWorkbook() → New Excel Workbook + Error Report
+```
+
+## Key Concepts
+
+### Conditional Logic Syntax
+
+Conditions use a specific syntax for product selection:
+- **Atoms**: `key=value` or `key!=value` (e.g., `gclj=M20`, `jycz=1`)
+- **AND**: Cartesian product of sets (e.g., `gclj=M20 AND jycz=1`)
+- **OR**: Union of sets (e.g., `azxs=A0 OR azxs=AT`)
+- **Parentheses**: Nested grouping (e.g., `(azxs=A0 OR azxs=AT) AND jycz=1`)
+
+Example: `gclj=M20 AND jycz=1 AND lcfw=M01 AND (azxs=A0 OR azxs=AT OR azxs=AH)`
+
+### Column Mapping (M04_Config)
+
+Source data must have columns in this order:
+- Column C (3): CODE (代号)
+- Column D (4): NAME (名称)
+- Column E (5): QTY (数量)
+- Column F (6): CONDITION (选择条件)
+- Column H (8): CATEGORY (类别)
+
+Data starts from row 4.
+
+### Category-Based Output
+
+Results are automatically organized by category (部件, 接头, 弹性元件, etc.). Each category gets a separate worksheet in the output workbook with columns dynamically ordered based on detected configuration keys.
+
+## Development Commands
+
+### Running the BOM Converter
+
+1. Open `YTHN-100.xlsm` in Excel
+2. Ensure "平台配置清单" worksheet exists with proper data
+3. Run `M01_Main.RunBOMConversion()` or execute from the Excel interface
+
+### Running Tests
+
+In Excel VBA Immediate Window (Ctrl+G):
+```
+RunAllTests
+```
+
+This runs unit tests for:
+- Simple atom parsing (`key=value`)
+- AND operations with Cartesian products
+- OR operations with union operations
+- Nested parentheses handling
+- Logic conflict detection
+
+### Python Skills (Claude Code Integration)
+
+The project includes custom skills in `.claude/skills/`:
+
+- **excel-to-markdown**: Convert Excel files to Markdown tables
+  ```bash
+  python3 .claude/skills/excel-to-markdown/scripts/excel_to_markdown.py <file.xlsx>
+  ```
+
+- **mermaid-diagrams**: Generate architecture diagrams using Mermaid syntax
+
+## Configuration
+
+### Header Priority Ordering
+
+Output columns are sorted according to priority defined in `M04_Config.GetHeaderPriority()`:
+1. azxs (安装形式)
+2. bkxs (表壳形式)
+3. gclj (过程连接)
+4. jycz (介质材质)
+5. lcdw (量程单位)
+6. lcfw (量程范围)
+7. fjgn (非公/耐震)
+8. btcy (表头尺寸)
+9. bp (表盘)
+10. dskd (度视宽度)
+11. nqlc (耐震连接)
+12. bptx (表盘图形)
+13. jddj (精度等级)
+14. cpdm (产品代码)
+15. tsjz (特殊基准)
+16. tsyq (特殊要求)
+17. bpts (特殊表盘)
+18. kdxh (壳体型号)
+
+Unknown keys are assigned priority 999 and appear last.
+
+## Git Workflow
+
+### Branches
+
+- **Main branch**: `DEV_YTHN-100`
+- **Current branch**: `NEW_BOM`
+
+### Claude Code Permissions
+
+Configured in `.claude/settings.local.json`:
+- Git operations: push, checkout, add
+- Python execution
+- Tree viewing and search utilities
+
+### NTFY Notifications
+
+The repository uses NTFY for git push notifications. Repository name is extracted dynamically from `github.repository` in workflow files.
+
+## File Structure
+
+```
+AutoBOM/
+├── VBA/
+│   ├── Modules/          # Procedural modules (M01-M99)
+│   └── ClassModules/     # OOP components (clsErrorLogger)
+├── .claude/
+│   └── skills/           # Claude Code integration skills
+├── reference_docs/       # Documentation and examples
+└── YTHN-100.xlsm/.xlsx  # Main workbook files
+```
+
+## Error Handling
+
+The system uses `clsErrorLogger` for comprehensive error tracking:
+- Errors are logged but do not stop processing
+- Final error report is generated in the output workbook
+- Context is preserved for debugging (row number, expression, details)
+
+## Important Notes
+
+- **Late Binding**: VBA modules use late binding (CreateObject) to avoid external reference dependencies
+- **Operator Precedence**: AND is processed before OR, parentheses override default precedence
+- **Recursive Parsing**: Nested expressions are handled recursively in M03_Logic
+- **Dynamic Columns**: Output workbooks detect and include only relevant configuration keys