Add initial project structure and core functionality for ArchDoc

- Created `.gitignore` files for various directories to exclude unnecessary files.
- Added `PLAN.md` to outline the project goals and architecture documentation generation.
- Implemented the `archdoc-cli` with a command-line interface for initializing and generating documentation.
- Developed the `archdoc-core` library for analyzing Python projects and generating architecture documentation.
- Included caching mechanisms to optimize repeated analysis.
- Established a comprehensive test suite to ensure functionality and error handling.
- Updated `README.md` to provide an overview and installation instructions for ArchDoc.

README.md

@@ -0,0 +1,101 @@
+# ArchDoc
+
+ArchDoc is a tool for automatically generating architecture documentation for Python projects. It analyzes your Python codebase and creates comprehensive documentation that helps developers understand the structure, dependencies, and key components of the project.
+
+## Features
+
+- **Automatic Documentation Generation**: Automatically generates architecture documentation from Python source code
+- **AST-Based Analysis**: Uses Python AST to extract imports, definitions, and function calls
+- **Diff-Aware Updates**: Preserves manual content while updating generated sections
+- **Caching**: Caches analysis results for faster subsequent runs
+- **Configurable**: Highly configurable through `archdoc.toml`
+- **Template-Based Rendering**: Uses Handlebars templates for customizable output
+
+## Installation
+
+To install ArchDoc, you'll need Rust installed on your system. Then run:
+
+```bash
+cargo install --path archdoc-cli
+```
+
+## Usage
+
+### Initialize Configuration
+
+First, initialize the configuration in your project:
+
+```bash
+archdoc init
+```
+
+This creates an `archdoc.toml` file with default settings.
+
+### Generate Documentation
+
+Generate architecture documentation for your project:
+
+```bash
+archdoc generate
+```
+
+This will create documentation files in the configured output directory.
+
+### Check Documentation Consistency
+
+Verify that your documentation is consistent with the code:
+
+```bash
+archdoc check
+```
+
+## Configuration
+
+ArchDoc is configured through an `archdoc.toml` file. Here's an example configuration:
+
+```toml
+[project]
+root = "."
+out_dir = "docs/architecture"
+entry_file = "ARCHITECTURE.md"
+language = "python"
+
+[scan]
+include = ["src"]
+exclude = [".venv", "venv", "__pycache__", ".git", "dist", "build"]
+
+[python]
+src_roots = ["src"]
+include_tests = true
+parse_docstrings = true
+
+[analysis]
+resolve_calls = true
+detect_integrations = true
+
+[output]
+single_file = false
+per_file_docs = true
+create_directories = true
+
+[caching]
+enabled = true
+cache_dir = ".archdoc/cache"
+max_cache_age = "24h"
+```
+
+## How It Works
+
+1. **Scanning**: ArchDoc scans your project directory for Python files based on the configuration
+2. **Parsing**: It parses each Python file using AST to extract structure and relationships
+3. **Analysis**: It analyzes the code to identify imports, definitions, and function calls
+4. **Documentation Generation**: It generates documentation using templates
+5. **Output**: It writes the documentation to files, preserving manual content
+
+## Contributing
+
+Contributions are welcome! Please feel free to submit a Pull Request.
+
+## License
+
+This project is licensed under the MIT License - see the LICENSE file for details.