refactor to src folder

frontend/www/bootstrap.js

@@ -14,7 +14,7 @@ if (typeof mergeInto !== 'undefined') mergeInto(LibraryManager.library, {
     }
 });
 
-import ("./index.js")
+import ("./src/index.js")
 .then(e => {
         h = e.handle;
     })

frontend/www/src/index.ts

@@ -141,6 +141,7 @@ class GameInstance {
         // Setup key handling
         document.addEventListener('keydown', this.handleKey.bind(this));
 
+        // List of [(x, y, r)] for all planets
         const planets = f32v(game.get_planets(), this.planet_count * 3);
 
         for (let i = 0; i < this.planet_count; i++) {