Adds image processing and GeoJSON creation

The commit adds necessary packages to the Replit environment (`.replit`), processes uploaded images to generate GeoJSON files (`processed/*.geojson`), and outputs processed images (`processed/*.png`).

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: c7b687d7-8856-49d8-87a3-9d7f3f6499f6
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/d7727d0d-3b25-49de-9476-c76c61abfa65/ca9da14f-2c8d-406c-92cb-0b548eb7aede.jpg

.replit

@@ -2,6 +2,7 @@ modules = ["python-3.11"]
 
 [nix]
 channel = "stable-24_05"
+packages = ["freetype", "lcms2", "libGL", "libGLU", "libimagequant", "libjpeg", "libtiff", "libwebp", "libxcrypt", "openjpeg", "tcl", "tk", "zlib"]
 
 [deployment]
 deploymentTarget = "autoscale"