UPDATE: split the webapp in a widget and the app itself

This splits the webapp in:

* IronCalc (the widget to be published on npmjs)
* The frontend for our "service"
* Adds "dummy code" for the backend using sqlite

webapp/IronCalc/biome.json

@@ -0,0 +1,18 @@
+{
+  "organizeImports": { "enabled": true },
+  "linter": {
+    "enabled": true,
+    "rules": {
+      "correctness": { "noUnusedImports": "error" }
+    }
+  },
+  "formatter": {
+    "indentStyle": "space",
+    "indentWidth": 2
+  },
+  "css": {
+    "formatter": {
+      "enabled": true
+    }
+  }
+}