Refactor StyledThemeProvider with improved comments

Updated comments for clarity and added a fallback for SSR-injected CSS variables during hydration.

Signed-off-by: Ankit Rewar <171806101+AnkitRewar11@users.noreply.github.com>

Author: AnkitRewar11

src/theme/app/StyledThemeProvider.js

@@ -12,9 +12,9 @@ export const StyledThemeProvider = (props) => {
   const { children, darkTheme, lightTheme } = props;
   const { isDark, didLoad } = useContext(ThemeManagerContext);
 
-  // For SSR, we need to provide a consistent theme initially
-  // This ensures the server and client render the same thing initially
   const currentTheme = isDark ? darkTheme : lightTheme;
+  
+  // Fallback to SSR-injected CSS variables during hydration to prevent FOUC.
   const theme = {
     ...(didLoad ? currentTheme : transformTheme(currentTheme)),
   };
@@ -26,7 +26,8 @@ export const StyledThemeProvider = (props) => {
   );
 };
 
-// Maps JS theme object to raw CSS variables (--key) initialized via onRenderBody.const transformTheme = (theme) => {
+// Maps JS theme object to raw CSS variables (--key) initialized via onRenderBody.
+const transformTheme = (theme) => {
   const newTheme = {};
   Object.keys(theme).forEach((key) => {
     const value = theme[key];