cli: document help (#179)

Author: aviau

docs/sdk/cli.mdx

@@ -35,7 +35,14 @@ export FLARE_API_KEY="<api-key>"
 export FLARE_TENANT_ID="<tenant-id>"
 ```
 
-## Usage Examples
+## Features
+
+## Discovering Commands
+
+You may discover all commands using `help`:
+```bash
+uvx flareio-cli help
+```
 
 ### Exporting Tenant Events