add Solar System Simulation to showcase

Author: vislupus

content/videos/challenges/7-solar-system-2d/showcase/contribution4.json

@@ -0,0 +1,9 @@
+{
+  "title": "Solar System Simulation",
+  "author": {
+    "name": "Nikola Bozhinov",
+    "url": "https://github.com/vislupus"
+  },
+  "url": "https://vislupus.github.io/p5-simulations/solar_system.html",
+  "submittedOn": "2025-01-10"
+}