feat: implemented chord guide customization feature

src/App.tsx

@@ -13,6 +13,8 @@ import LoadingOverlay from './components/common/LoadingOverlay';
 import { useEffect as useEffectReact, useState, useRef } from 'react';
 import { KGToneBuffersPool } from './core/audio-interface/KGToneBuffersPool';
 import { KGCore } from './core/KGCore';
+import { ConfigManager } from './core/config/ConfigManager';
+import { validateFunctionalChordsJSON } from './util/scaleUtil';
 
 function App() {
   // Enable global keyboard handler for copy/paste and undo/redo
@@ -40,6 +42,9 @@ function App() {
       // Load the current project from KGCore
       loadProject(null);
 
+      // Initialize ConfigManager first to load config.json and user settings
+      await ConfigManager.instance().initialize();
+
       // Initialize store from config after ConfigManager is ready
       await initializeFromConfig();
 
@@ -53,13 +58,31 @@ function App() {
           functionalChordsResponse.json()
         ]);
 
-        // Store functional chords data (includes name, steps, T/S/D groups, and chord notes for each mode)
-        KGCore.FUNCTIONAL_CHORDS_DATA = functionalChordsData;
-        console.log(`Loaded functional chords for ${Object.keys(functionalChordsData).length} modes`);
+        // Store original functional chords data
+        KGCore.ORIGINAL_FUNCTIONAL_CHORDS_DATA = functionalChordsData;
+        console.log(`Loaded original functional chords for ${Object.keys(functionalChordsData).length} modes`);
+
+        // Check if custom chord definition exists and is valid
+        const configManager = ConfigManager.instance();
+        const customDefinition = configManager.get('chord_guide.chord_definition') as string;
+
+        if (customDefinition && customDefinition.trim()) {
+          const validationResult = validateFunctionalChordsJSON(customDefinition);
+          if (validationResult.valid) {
+            KGCore.FUNCTIONAL_CHORDS_DATA = JSON.parse(customDefinition);
+            console.log('Using custom chord definition from settings');
+          } else {
+            KGCore.FUNCTIONAL_CHORDS_DATA = functionalChordsData;
+            console.log('Custom chord definition invalid, using original');
+          }
+        } else {
+          KGCore.FUNCTIONAL_CHORDS_DATA = functionalChordsData;
+          console.log('No custom chord definition, using original');
+        }
       } catch (error) {
         console.error('Failed to load mode/chord data:', error);
         // Fallback to defaults
-        KGCore.FUNCTIONAL_CHORDS_DATA = {
+        const fallbackData = {
           ionian: {
             name: 'Ionian',
             steps: [2, 2, 1, 2, 2, 2, 1],
@@ -69,6 +92,8 @@ function App() {
             chords: {}
           }
         };
+        KGCore.ORIGINAL_FUNCTIONAL_CHORDS_DATA = fallbackData;
+        KGCore.FUNCTIONAL_CHORDS_DATA = fallbackData;
       }
 
       // Log maxBars after initialization completes