Create application/tasks directory if not exists

This is not a `Place` folder but related one

Closes: #1878
Refs: #1617

lib/planner.js

@@ -16,6 +16,7 @@ class Planner {
   }
 
   async init() {
+    await metarhia.metautil.ensureDirectory(this.path);
     const now = metarhia.metautil.nowDate();
     try {
       const files = await node.fsp.readdir(this.path, { withFileTypes: true });