style: sort Python imports with isort

Add isort configuration (profile=black, line_length=100) to pyproject.toml,
add isort pre-commit hook, and auto-sort imports across all Python source files.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

python/resources/resource_definitions.py

@@ -5,10 +5,10 @@ Resources follow the MCP 2025-06-18 specification, providing
 read-only access to project data for LLM context.
 """
 
-import json
 import base64
-from typing import Dict, Any, List, Optional
+import json
 import logging
+from typing import Any, Dict, List, Optional
 
 logger = logging.getLogger("kicad_interface")