chore(docs): explain purpose of createContext argument

Author: KatoakDR

electron/renderer/context/game.tsx

@@ -22,6 +22,10 @@ export interface GameContextValue {
   todo?: true;
 }
 
+/**
+ * Defines shape and behavior of the context value
+ * when no provider is found in the component hierarchy.
+ */
 export const GameContext = createContext<GameContextValue>({});
 
 GameContext.displayName = 'GameContext';

electron/renderer/context/logger.tsx

@@ -16,6 +16,10 @@ export interface LoggerContextValue {
   logger: Logger;
 }
 
+/**
+ * Defines shape and behavior of the context value
+ * when no provider is found in the component hierarchy.
+ */
 export const LoggerContext = createContext<LoggerContextValue>({
   logger: defaultLogger,
 });

electron/renderer/context/theme.tsx

@@ -16,7 +16,14 @@ export interface ThemeContextValue {
   setColorMode?: (colorMode: EuiThemeColorMode) => void;
 }
 
-export const ThemeContext = createContext<ThemeContextValue>({});
+/**
+ * Defines shape and behavior of the context value
+ * when no provider is found in the component hierarchy.
+ */
+export const ThemeContext = createContext<ThemeContextValue>({
+  colorMode: getThemeName(),
+  setColorMode: setThemeName,
+});
 
 ThemeContext.displayName = 'ThemeContext';