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/Epub/Epub/Section.h

@@ -33,7 +33,6 @@ class Section {
   bool clearCache() const;
   bool createSectionFile(int fontId, float lineCompression, bool extraParagraphSpacing, uint8_t paragraphAlignment,
                          uint16_t viewportWidth, uint16_t viewportHeight, bool hyphenationEnabled,
-                         const std::function<void()>& progressSetupFn = nullptr,
-                         const std::function<void(int)>& progressFn = nullptr);
+                         const std::function<void()>& popupFn = nullptr);
   std::unique_ptr<Page> loadPageFromSectionFile();
 };