feat(ui): change popup logic (#442)

## Summary

* refactors Indexing popups into ScreenComponents (they had different
implementations in different files)
* removes Indexing popup for small chapters
* only show Indexing popup (without progress bar) for large chapters
(using same minimum file size condition as for progress bar before)

## Additional Context

* Having to show even single popup message and redraw the screen slows
down the flow significantly
* Testing results:
    * Opening large chapter with progress bar - 11 seconds
* Same chapter without progress bar, only single Indexing popup - 5
seconds

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### AI Usage

Did you use AI tools to help write this code? _**< PARTIALLY>**_

lib/GfxRenderer/GfxRenderer.h

@@ -56,7 +56,7 @@ class GfxRenderer {
   int getScreenHeight() const;
   void displayBuffer(HalDisplay::RefreshMode refreshMode = HalDisplay::FAST_REFRESH) const;
   // EXPERIMENTAL: Windowed update - display only a rectangular region
-  void displayWindow(int x, int y, int width, int height) const;
+  // void displayWindow(int x, int y, int width, int height) const;
   void invertScreen() const;
   void clearScreen(uint8_t color = 0xFF) const;