Add comprehensive GIS features: attribute table, style editor, exports, and more

[giswqs]

Summary

This PR adds comprehensive GIS features to AnyMap Studio, transforming it into a full-featured desktop GIS application.

New Features

Layer Management

• Attribute Table: View and inspect feature properties in a searchable, sortable table
• Style Editor: Customize layer appearance (fill color, stroke, opacity, labels)
• Layer Groups: Organize layers into expandable/collapsible groups
• Enhanced Layer Context Menu: Zoom to layer, edit style, view attributes, duplicate, rename

Navigation & Tools

• Go To Coordinates: Jump to any location by entering lat/lng coordinates
• Command Palette: Quick access to all commands via Ctrl+Shift+P
• Identify Tool: Click features to view their properties
• Keyboard Shortcuts: I (identify), M (measure), Escape (cancel)

Export Capabilities

• Export Dialog: Export map as PNG, JPEG, or GeoJSON
• Multiple Output Formats: Image export with configurable quality

UI Improvements

• Settings Panel: Configure coordinate format (decimal/DMS), status bar visibility
• Enhanced Toolbar: Added identify, export, coordinates, and command palette buttons
• Improved Status Bar: Shows coordinates in configurable format with copy-to-clipboard
• Fixed Basemap Switching: Layers now properly preserved when changing basemaps

Data Support

• URL Loading: Load data from URLs (GeoJSON, COG, PMTiles, XYZ tiles)
• Enhanced Parsers: Better error handling for various data formats

Files Changed

• 20 files changed, 2924 insertions, 233 deletions

Test Plan

• Open app and verify landing page displays
• Add a GeoJSON layer from file
• Test basemap switching (layers should persist)
• Test identify tool on features
• Test attribute table display
• Test style editor (change colors, opacity)
• Test coordinate navigation (Ctrl+G)
• Test command palette (Ctrl+Shift+P)
• Test PNG/JPEG export
• Test keyboard shortcuts (I, M, Escape)