feat: enhance drawing capabilities with new brush types

[Shreyanshi210205]

Description

This pull request introduces a complete brush system overhaul featuring multiple new and enhanced brush types — including realistic texture simulation and smoother rendering.
It also resolves previous merge conflicts that caused brush state resets and visual inconsistencies across drawing tools.

What's New

• Added New Brushes:

  • Dashed Brush – Scales correctly with line width, maintaining consistent dash spacing.
  • Paint Brush – Thick, with creamy, blended texture and natural diffusion.
  • Crayon Brush – Grainy wax texture with layered pigment buildup.
  • Oil Pastel Brush – Soft pigment blending with organic irregularity and subtle opacity variation.

• Improvements & Fixes:

  • Fixed brush rendering issues introduced by previous merges.
  • Unified brush rendering within drawShape() to ensure consistent context restoration.
  • Reduced brush jitter using deterministic pseudo-random jitter generation.
  • Improved paint brush behavior at smaller widths - texture and softness now preserved.
  • Optimized multi-layer compositing for smoother transitions and realistic blending.

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Semver Changes

• Patch (bug fix, no new features)
• Minor (new features, no breaking changes)
• Major (breaking changes)

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Issues

#45

Checklist

• I have read the Contributing Guidelines