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.

test-project/src/core.py

@@ -0,0 +1,42 @@
+"""Core module with database and HTTP integrations."""
+
+import sqlite3
+import requests
+
+class DatabaseManager:
+    """Manages database connections and operations."""
+    
+    def __init__(self, db_path: str):
+        self.db_path = db_path
+        self.connection = None
+    
+    def connect(self):
+        """Connect to the database."""
+        self.connection = sqlite3.connect(self.db_path)
+    
+    def execute_query(self, query: str):
+        """Execute a database query."""
+        if self.connection:
+            cursor = self.connection.cursor()
+            cursor.execute(query)
+            return cursor.fetchall()
+
+def fetch_external_data(url: str) -> dict:
+    """Fetch data from an external API."""
+    response = requests.get(url)
+    return response.json()
+
+def process_user_data(user_id: int) -> dict:
+    """Process user data with database and external API calls."""
+    # Database interaction
+    db = DatabaseManager("users.db")
+    db.connect()
+    user_data = db.execute_query(f"SELECT * FROM users WHERE id = {user_id}")
+    
+    # External API call
+    api_data = fetch_external_data(f"https://api.example.com/users/{user_id}")
+    
+    return {
+        "user": user_data,
+        "api": api_data
+    }