chore: set up pre-commit framework with general hooks

Add .pre-commit-config.yaml with pre-commit-hooks v5.0.0 (trailing
whitespace, end-of-file fixer, yaml/json checks, large file guard,
merge conflict detection). Add minimal pyproject.toml. Auto-fix
trailing whitespace and missing end-of-file newlines across the
codebase.

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

python/commands/library_schematic.py

@@ -31,7 +31,7 @@ class LibraryManager:
         # Extract library names from paths
         library_names = [os.path.splitext(os.path.basename(lib))[0] for lib in libraries]
         print(f"Found {len(library_names)} libraries: {', '.join(library_names[:10])}{'...' if len(library_names) > 10 else ''}")
-        
+
         # Return both full paths and library names
         return {"paths": libraries, "names": library_names}
 
@@ -43,7 +43,7 @@ class LibraryManager:
             # without loading each one. We might need to implement this using KiCAD's Python API
             # directly, or by using a different approach.
             # For now, this is a placeholder implementation.
-            
+
             # A potential approach would be to load the library file using KiCAD's Python API
             # or by parsing the library file format.
             # KiCAD symbol libraries are .kicad_sym files which are S-expression format
@@ -73,23 +73,23 @@ class LibraryManager:
             # 1. Getting a list of all libraries using list_available_libraries
             # 2. For each library, getting a list of all symbols
             # 3. Filtering symbols based on the query
-            
+
             # For now, this is a placeholder implementation
             libraries = LibraryManager.list_available_libraries(search_paths)
-            
+
             results = []
             print(f"Searched for symbols matching '{query}'. This requires advanced implementation.")
             return results
         except Exception as e:
             print(f"Error searching for symbols matching '{query}': {e}")
             return []
-            
+
     @staticmethod
     def get_default_symbol_for_component_type(component_type, search_paths=None):
         """Get a recommended default symbol for a given component type"""
         # This method provides a simplified way to get a symbol for common component types
         # It's useful when the user doesn't specify a particular library/symbol
-        
+
         # Define common mappings from component type to library/symbol
         common_mappings = {
             "resistor": {"library": "Device", "symbol": "R"},
@@ -103,19 +103,19 @@ class LibraryManager:
             "microcontroller": {"library": "MCU_Module", "symbol": "Arduino_UNO_R3"},
             # Add more common components as needed
         }
-        
+
         # Normalize input to lowercase
         component_type_lower = component_type.lower()
-        
+
         # Try direct match first
         if component_type_lower in common_mappings:
             return common_mappings[component_type_lower]
-            
+
         # Try partial matches
         for key, value in common_mappings.items():
             if component_type_lower in key or key in component_type_lower:
                 return value
-                
+
         # Default fallback
         return {"library": "Device", "symbol": "R"}
 
@@ -127,15 +127,15 @@ if __name__ == '__main__':
         first_lib = libraries["paths"][0]
         lib_name = libraries["names"][0]
         print(f"Testing with first library: {lib_name} ({first_lib})")
-        
+
         # List symbols in the first library
         symbols = LibraryManager.list_library_symbols(first_lib)
         # This will report that it requires advanced implementation
-        
+
     # Get default symbol for a component type
     resistor_sym = LibraryManager.get_default_symbol_for_component_type("resistor")
     print(f"Default symbol for resistor: {resistor_sym['library']}/{resistor_sym['symbol']}")
-    
+
     # Try a partial match
     cap_sym = LibraryManager.get_default_symbol_for_component_type("cap")
     print(f"Default symbol for 'cap': {cap_sym['library']}/{cap_sym['symbol']}")