Update docs for auth-id changes

- Replace "headscale nodes register" with "headscale auth register"
- Update from registration key to Auth ID
- Fix API example to register a node

docs/ref/api.md

@@ -54,8 +54,8 @@ Headscale server at `/swagger` for details.
 
     ```console
     curl -H "Authorization: Bearer <API_KEY>" \
-        -d user=<USER> -d key=<REGISTRATION_KEY> \
-        https://headscale.example.com/api/v1/node/register
+        --json '{"user": "<USER>", "authId": "AUTH_ID>"}' \
+        https://headscale.example.com/api/v1/auth/register
     ```
 
 ## gRPC

docs/ref/registration.md

@@ -48,10 +48,10 @@ headscale users create <USER>
     ```
 
     Usually, a browser window with further instructions is opened. This page explains how to complete the registration
-    on your Headscale server and it also prints the registration key required to approve the node:
+    on your Headscale server and it also prints the Auth ID required to approve the node:
 
     ```console
-    headscale nodes register --user <USER> --key <REGISTRATION_KEY>
+    headscale auth register --user <USER> --auth-id <AUTH_ID>
     ```
 
     Congrations, the registration of your personal node is complete and it should be listed as "online" in the output of
@@ -79,10 +79,10 @@ headscale users create <USER>
     ```
 
     Usually, a browser window with further instructions is opened. This page explains how to complete the registration
-    on your Headscale server and it also prints the registration key required to approve the node:
+    on your Headscale server and it also prints the Auth ID required to approve the node:
 
     ```console
-    headscale nodes register --user <USER> --key <REGISTRATION_KEY>
+    headscale auth register --user <USER> --auth-id <AUTH_ID>
     ```
 
     Headscale checks that `<USER>` is allowed to register a node with the specified tag(s) and then transfers ownership

docs/ref/tags.md

@@ -45,10 +45,10 @@ tailscale up --login-server <YOUR_HEADSCALE_URL> --advertise-tags= --force-reaut
 ```
 
 Usually, a browser window with further instructions is opened. This page explains how to complete the registration on
-your Headscale server and it also prints the registration key required to approve the node:
+your Headscale server and it also prints the Auth ID required to approve the node:
 
 ```console
-headscale nodes register --user <USER> --key <REGISTRATION_KEY>
+headscale auth register --user <USER> --auth-id <AUTH_ID>
 ```
 
 All previously assigned tags get removed and the node is now owned by the user specified in the above command.

docs/usage/getting-started.md

@@ -110,19 +110,19 @@ tailscale up --login-server <YOUR_HEADSCALE_URL>
 ```
 
 Usually, a browser window with further instructions is opened. This page explains how to complete the registration on
-your headscale server and it also prints the registration key required to approve the node:
+your headscale server and it also prints the Auth ID required to approve the node:
 
 === "Native"
 
     ```shell
-    headscale nodes register --user <USER> --key <REGISTRATION_KEY>
+    headscale auth register --user <USER> --auth-id <AUTH_ID>
     ```
 
 === "Container"
 
     ```shell
     docker exec -it headscale \
-      headscale nodes register --user <USER> --key <REGISTRATION_KEY>
+      headscale auth register --user <USER> --auth-id <AUTH_ID>
     ```
 
 ### [Pre authenticated key](../ref/registration.md#pre-authenticated-key)