fix: [GRWT-3474] Point_Highlight_Enlarges_when_navigating_back_to_same_chart_view

[ilya-deriv]

https://app.clickup.com/t/20696747/GRWT-3474

This PR contains the following changes:

• ✨ New feature (non-breaking change which adds functionality)
• 🛠️ Bug fix (non-breaking change which fixes an issue)
• ❌ Breaking change (fix or feature that would cause existing functionality to change)
• 🧹 Code refactor
• ✅ Build configuration change
• 📝 Documentation
• 🗑️ Chore

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@ramin-deriv

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[ramin-deriv]

Is this going to change how line drawing will look like on the web, if so, we should consider not affecting the web.
either by giving customization options, and having default values as something that keeps the appearance of the drawing tool
or other options it to create our mobile version line drawing class which is preferred. if we see the behavior of it is too much different from the web implementation

[ramin-deriv]

Shouldn't we create an instance of MobileLineDrawingToolLabelPainter here?

 final LineDrawingToolConfigMobile lineConfig = config as LineDrawingToolConfigMobile;

    if (_startPoint == null || _endPoint == null) {
      return;
    }

    if (drawingData.isSelected && drawingData.isDrawingFinished) {
      final MobileLineDrawingToolLabelPainter? _lineDrawingToolLabelPainter =
          MobileLineDrawingToolLabelPainter(
        lineConfig,
        startPoint: _startPoint!,
        endPoint: _endPoint!,
      );

      _lineDrawingToolLabelPainter?.paint(canvas, size, chartConfig, epochFromX,
          quoteFromY, epochToX, quoteToY);

[ramin-deriv]

I think for the web version which is LineDrawing class, the labelPainter was being returned as null.
so we didn't paint anything in line _lineDrawingToolLabelPainter?.paint(canvas, size, chartConfig, epochFromX, quoteFromY, epochToX, quoteToY); because it was null. then we can remove it. and onLabelPaint in LineDrawing will become:

  @override
  void onLabelPaint(
    Canvas canvas,
    Size size,
    ChartTheme theme,
    ChartConfig chartConfig,
    int Function(double x) epochFromX,
    double Function(double) quoteFromY,
    double Function(int x) epochToX,
    double Function(double y) quoteToY,
    DrawingToolConfig config,
    DrawingData drawingData,
    DataSeries<Tick> series,
  ) {}

[ramin-deriv]

Actually it's not a mandator override, in LineDrawing we can just remove the onLabelPaint method override, doesn't have to have empty override