UPDATE: Adds web app (#79)

Things missing:

* Browse mode
* Front end tests
* Storybook

webapp/README.md

@@ -0,0 +1,58 @@
+# IronCalc Web App
+
+The webapp is build with React and TypeScript. We use icons from [Lucide](https://lucide.dev/)
+
+## Build
+
+First thing build the wasm is the `../bindings/wasm` folder.
+
+If you have nodejs installed you just need to:
+
+```bash
+npm install
+```
+
+## Local development
+
+
+```bash
+npm run dev
+```
+
+## Linter and formatting
+
+We use [biome](https://biomejs.dev/):
+
+```
+npm run check
+```
+
+Will check for linter and formatting issues.
+
+## Testing
+
+We use vitest. Simply:
+
+```
+npm run test
+```
+
+Warning: There is only the testing infrastructure in place.
+
+## Deploy
+
+Deploying is a bit of a manual hassle right now:
+To build a deployable frontend:
+
+```bash
+npm run build
+```
+
+Please copy the `inroncalc.svg` icon and the models you want to have as 'examples' in the internal 'ic' format.
+I normally compress the wasm and js files with brotli
+
+```
+brotli wasm_bg-*****.wasm
+```
+
+Copy to the final destination and you are good to go.