fix: Update Seekbar Position Logic (#535)

* fix slider displays uncorrectly, rearrange seekbar props

* Removal contensize variable, using math to solve.
Also need percen of device height as float.
Format readerscreen.js easilier to read (at least for me :>)

* set loadding when "scroll to" is unnecessary

* enable scroll even on loading (no making re-rerender)

* add attributes to chapter element for custom css

* shorten variable name. remove unuse function

* seekbar display more correctly for webview.
removal duplicate var

* trying to removal webViewScroll state

* Seekbar should work properly.
Need to implement save position.
And sync TextView and WebView

* just rearrange props to make easier for handling

* using state currentScroll instead of scrollPercentage

* share offsetY between text and web view.
Still issue when turn back from web to text. It cant scroll back.

* this should work well, unless users touch so fast

* clean up code

* use Promise.all instead

* the same logic but shoten code

* not saving croll when closing layout