chore: initial checkpoint - Tesla Roadtrip planner

- Proactive Grok integration (xAI API + local CLI fallback)
- Real road routing via OSRM (no more bird's-eye lines)
- Heavy structured logging for fast iteration
- Strong sanitization + geocoding + ErrorBoundary (no black screens)
- Playwright E2E tests (API diagnostic + full UI flow)
- scripts/dev.sh for one-command startup
- Clean .env.example + documentation

This is a stable checkpoint before further prompt/UI refinement.

atlas.hcl

@@ -0,0 +1,13 @@
+data "external_schema" "prisma" {
+  program = ["npx", "prisma", "migrate", "diff", "--from-empty", "--to-schema", "prisma/schema.prisma", "--script"]
+}
+
+env "dev" {
+  url = getenv("DATABASE_URL")
+  dev = getenv("ATLAS_DEV_URL")
+  schema { src = data.external_schema.prisma.url }
+  migration {
+    dir = "file://atlas/migrations"
+    exclude = ["_prisma_migrations"]
+  }
+}