docs: Improve contributing.md, add incident instructions INTER-945

contributing.md

@@ -1,27 +1,39 @@
 # Contributing to Fingerprint Pro use cases
 
+The `main` branch is locked for the push action. For proposing changes, use the standard [pull request approach](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/creating-a-pull-request). It's recommended to discuss fixes or new functionality in the Issues, first.
+
 ## Working with code
 
 We prefer using [yarn](https://yarnpkg.com/) for installing dependencies and running scripts.
 
-The `main` branch is locked for the push action. For proposing changes, use the standard [pull request approach](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/creating-a-pull-request). It's recommended to discuss fixes or new functionality in the Issues, first.
+* Run `yarn install` to install dependencies.
+* Run `yarn dev` to start the local development server.
+* Run `yarn build` to build a production build of the project.
+* Run `yarn start` to start the production build of the project.
+* Run `yarn lint` to check the code style using [ESLint](https://eslint.org/).
+
+See the [package.json](./package.json) -> `scripts` section for more useful commands.
 
-### How to build
+## Testing
 
-Just run:
+* Run `yarn test` to run unit tests using [Vitest](https://vitest.dev/).
+* To run end-to-end tests using [Playwright](https://playwright.dev/):
+  *  First run `yarn dev` or `yarn start` to start the development or production server. 
+  *  Then run `yarn test:e2e:chrome` to run the tests in Chrome.
 
-```shell
-yarn build
-```
+### Deployment
 
-### Code style
+- Merging a PR into `main` automatically triggers a new deployment accessible on [demo.fingerprint.com](https://demo.fingerprint.com).
+- The app is deployed as a Digital Ocean App.
+- The app is deployed behind a Cloudfront distribution in the Fingerprint DEV AWS environment (search for `demo.fingerprint.com` in the distribution description).
+  - If you ever encounter caching issues, for example, a cached index.html pointing to no longer existing resources, you can fix it by [creating a cache invalidation](https://docs.aws.amazon.com/AmazonCloudFront/latest/DeveloperGuide/Invalidation_Requests.html#invalidating-objects-console) (`/*` is fine) in the Cloudfront distribution.
 
-The code style is controlled by [ESLint](https://eslint.org/). Run to check that the code style is ok:
+### Rollbacks and incident response
 
-```shell
-yarn lint
-```
+If an incident occurs, any member of the Fingerprint team on Digital Ocean can rollback the app to the previous version. In case of any problems, please contact @JuroUhlar and the Integrations team.
 
-### How to publish
+1. Go to the [Digital Ocean control panel](https://cloud.digitalocean.com/apps/69a24f2e-6d8e-4e9d-bcf3-024a653ae7b2/deployments).
+2. Find the `fingerprint-use-cases` app.
+3. Click on the `Activity` tab.
+4. Find a previous working version and click `Rollback`.
 
-- Project is deployed to [demo.fingerprint.com](https://demo.fingerprint.com) with each merge into the `main` branch.