refine unique name doc

docker/compose/zrok-public-reserved/compose.yml

@@ -38,7 +38,7 @@ services:
       STATE_DIRECTORY: /mnt  # zrok homedir in container
 
       # most relevant options
-      ZROK_UNIQUE_NAME:     # vanity share token is used to construct frontend subdomain, e.g. "myapp" for "myapp.in.zrok.io"
+      ZROK_UNIQUE_NAME:     # name is used to construct frontend domain name, e.g. "myapp" in "myapp.share.zrok.io"
       ZROK_BACKEND_MODE:    # web, caddy, drive, proxy
       ZROK_TARGET:          # backend target, is a path in container filesystem unless proxy mode
       ZROK_INSECURE:        # "--insecure" if proxy target has unverifiable TLS server certificate

docs/guides/_frontdoor-docker.mdx

@@ -22,6 +22,13 @@ When the project runs it will:
   ```bash title=".env"
   ZROK_ENABLE_TOKEN="8UL9-48rN0ua"
   ```
+1. Name the Share
+
+    This unique name becomes part of the domain name of the share, e.g. `https://my-prod-app.in.zrok.io`. A random name is generated if you don't specify one.
+
+    ```bash title=".env"
+    ZROK_UNIQUE_NAME="my-prod-app"
+    ```
 
 1. Run the Compose project to start sharing the built-in demo web server. Be sure to `--detach` so the project runs in the background if you want it to auto-restart when your computer reboots.
 

docs/guides/_frontdoor-linux.mdx

@@ -89,9 +89,9 @@ Save the enable token from the zrok console in the configuration file.
 ZROK_ENABLE_TOKEN="14cbfca9772f"
 ```
 
-## Choose a Vanity Share Token
+## Name your Share
 
-This becomes the leading part of the domain name of the share, e.g. `https://my-prod-app.in.zrok.io`.
+This unique name becomes part of the domain name of the share, e.g. `https://my-prod-app.in.zrok.io`. A random name is generated if you don't specify one.
 
 ```bash title="/opt/openziti/etc/zrok/zrok-share.env"
 ZROK_UNIQUE_NAME="my-prod-app"