Fix database seeding: include carOptions.json in server dir

The seed data file was referenced from Kenteken-Gen-1-main/ which
is not copied into the Docker image. Moved carOptions.json to
server/ so it's available in the container. Also added .gitignore
and removed node_modules and db files from tracking.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/node_modules/@mapbox/node-pre-gyp/lib/util/nw-pre-gyp/package.json

@@ -1,9 +0,0 @@
-{
-"main": "index.html",
-"name": "nw-pre-gyp-module-test",
-"description": "Node-webkit-based module test.",
-"version": "0.0.1",
-"window": {
-   "show": false
-}
-}