docs: initial CI setup

docs/getting_started.md

@@ -0,0 +1,14 @@
+# Getting Started
+
+## Deploying the operator
+
+The easiest way to deploy the operator is to fetch the manifest from the [releases](https://code.icb4dc0.de/prskr/supabase-operator/releases) and apply it like this:
+
+```bash
+kubectl apply --server-side -f manifest.yaml
+```
+
+The manifest is rendered as part of the release workflow and based on [kustomize](https://kustomize.io/).
+If you want to customize the deployment, you can start from the [release/default](https://code.icb4dc0.de/prskr/supabase-operator/src/branch/main/config/release/default) layer and build your own manifest.
+
+## Deploying a basic Supabase instance