Add petalbloom generative sketch

[msfeldstein]

New Sketch: Petal Bloom

Adds a new generative art sketch (sketches/petalbloom-2026.04.09-12.00.00.js) that creates organic, animated flower-like forms.

Features

• Radial symmetry with configurable petal count (5-12 petals per bloom)
• Multi-layered blooms — each flower has 5-8 overlapping petal layers with offset rotations
• Noise-driven organic shapes — petals use 3D simplex noise for natural-looking wobble and variation
• Multiple flowers — randomly places 3-6 blooms across the canvas with varying sizes and rotations
• Gradient fills — radial gradients on petals and flower centers for depth
• Ambient particles — floating sparkle particles orbit the composition
• Animated — gentle rotation and noise evolution over time
• Randomized color palettes — selects from warm, cool, pastel, and vibrant palettes

Technical Details

• Uses canvas-sketch with 2D canvas context (2048x2048)
• Uses the project's existing perlin.js noise module (simplex2 and simplex3)
• Follows the same file naming convention as existing sketches