Add: Native support for GeoJSON via geopandas with dashboard example

[sanjai-11]

---

name: Pull Request
about: Add built-in support for geospatial data using GeoPandas
title: "[Feature] Add GeoPandas Support for Geospatial Data Sources"
labels: enhancement
assignees: ''

Related Issue
Fixes #530

Description of Changes
This PR adds first-class support for geospatial data in Preswald using geopandas. Key updates include:

• Added support for type = "geojson" in preswald.toml
• Added flatten_geometry = true|false toggle for geometry handling
• Implemented load_geospatial_source() using geopandas.read_file() in data.py
• Automatically flattens geometries into GeoJSON via __geo_interface__ when enabled
• Supports .geojson, .shp, .gpkg file formats
• Added a new example at examples/geo/ with monuments_geo.geojson and interactive dashboard
• Ensured compatibility with get_df(), plotly(), table(), chat(), and map rendering

Type of Change

• New feature (non-breaking change which adds functionality)
• New example
• Bug fix
• Breaking change
• Documentation update
• Test improvement

Testing

• Ran the Preswald app with monuments_geo.geojson
• Validated data loading, filtering, mapping, and analytics
• Verified map location markers are correctly scaled by visitors
• Tested toggling flatten_geometry in preswald.toml
• Confirmed behavior with missing/malformed files
• Screenshots attached in issue discussion (see hover interaction and map rendering)

Screenshots

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (inline comments + example)
• My changes generate no new warnings
• I have run my code against examples and ensured no errors
• Any dependent changes have been merged and published in downstream modules

[sanjai-11]

Hi @amrutha97,
I've opened a PR addressing this issue: #530

The implementation adds native geopandas support as discussed, including:

1. type = "geojson" and "shapefile" support in preswald.toml
2. Automatic flattening of geometry using geo_interface
3. Configurable flatten_geometry option
4. A working example app under examples/geo/ with visualizations

Please have a look when you get a chance..