- Linting (ESLint): Update polyfills to new compat rules of

eslint-config-ash-nazg and adhere to new rules (prefer `for-of`
  (or array methods) to `for`, catch preferred `includes` to `indexOf`);
  avoid `no-zero-fractions` rule for now
- npm: Update devDeps (removing one unneeded)

editor/path.js

@@ -1282,15 +1282,14 @@ export class Path {
   */
   addPtsToSelection (indexes) {
     if (!Array.isArray(indexes)) { indexes = [indexes]; }
-    for (let i = 0; i < indexes.length; i++) {
-      const index = indexes[i];
+    indexes.forEach((index) => {
       const seg = this.segs[index];
       if (seg.ptgrip) {
         if (!this.selected_pts.includes(index) && index >= 0) {
           this.selected_pts.push(index);
         }
       }
-    }
+    });
     this.selected_pts.sort();
     let i = this.selected_pts.length;
     const grips = [];