feat: implemented chord guide customization feature

src/core/KGCore.ts

@@ -18,7 +18,8 @@ export class KGCore {
   private static _instance: KGCore | null = null;
 
   // Global music data resources
-  public static FUNCTIONAL_CHORDS_DATA: Record<string, { name: string; steps: number[]; T: string[]; S: string[]; D: string[]; chords: Record<string, string[]> }> = {}; // Functional chords by mode (T/S/D) with mode-specific chord notes, and mode metadata
+  public static ORIGINAL_FUNCTIONAL_CHORDS_DATA: Record<string, { name: string; steps: number[]; T: string[]; S: string[]; D: string[]; chords: Record<string, string[]> }> = {}; // Original functional chords loaded from functional_chords.json
+  public static FUNCTIONAL_CHORDS_DATA: Record<string, { name: string; steps: number[]; T: string[]; S: string[]; D: string[]; chords: Record<string, string[]> }> = {}; // Active functional chords (either original or custom from user settings)
 
   private currentProject: KGProject = new KGProject();
 

src/core/config/ConfigManager.ts

@@ -73,6 +73,9 @@ interface AppConfig {
   templates: {
     custom_instructions: string;
   };
+  chord_guide: {
+    chord_definition: string;
+  };
   [key: string]: unknown;
 }
 
@@ -228,6 +231,9 @@ export class ConfigManager {
         },
         templates: {
           custom_instructions: ''
+        },
+        chord_guide: {
+          chord_definition: ''
         }
       };
       console.log('Using fallback hardcoded config due to load error');