code-quality: LayerStylePanel.jsx at 1644 lines — style editor logic needs splitting

[evan-zhang11]

Problem

frontend/src/LayerStylePanel.jsx has grown to 1644 lines since the map editor was merged (commit 828e69b).

This single component handles:

• Fill/stroke/label style configuration
• Classification logic
• Color ramp selection
• Symbol wizard integration

Current size context

File	Lines
LayerStylePanel.jsx	1644
App.jsx	2186
MapEditor.jsx	701
styleJsonToOl.js	713

Related: #230 (App.jsx), #227 (handlers.rs), #229 (workspace_handlers.rs)

Suggested split

• FillStyleEditor.jsx — fill color, opacity, pattern
• StrokeStyleEditor.jsx — stroke color, width, dash
• LabelStyleEditor.jsx — font, size, placement
• ClassificationPanel.jsx — classification method, breaks, color ramp
• LayerStylePanel.jsx — orchestrator that composes the above

Impact

Low priority — functional but increasingly hard to maintain. Address before adding more style features.