hivectl: drop forge create-user; SSO makes a human's forge account

The forge now creates a human's account on their first authelia login,
so the verb has no job left. Deletes it, HostRequest::ForgeCreateUser,
its handler, provision_user_token, change_user_password and the hive's
TOKEN_SCOPES. change_user_password also passed the password as an
argument to `forgejo admin user change-password`, so it showed in the
container's process list.

ensure_user_exists and mint_token stay for the `core` bootstrap, their
one caller now. ensure_user_exists loses its password parameter: only the
deleted path set one.

Refs #3782

hive-host-sock/src/lib.rs

@@ -315,17 +315,6 @@ pub enum HostRequest {
         #[serde(default)]
         room: Option<String>,
     },
-    /// Create or refresh a forge account + API token for `name`. Daemon-side
-    /// equivalent of `hivectl forge create-user`: for a non-agent
-    /// (operator/human) it mints a user and returns the token in
-    /// [`HostResponse::messages`]. An existing agent is refused: its token is
-    /// swarm-controller's to mint. `password` is resolved client-side
-    /// (inline flag or stdin) and only meaningful for non-agent accounts.
-    ForgeCreateUser {
-        name: Ident,
-        #[serde(default)]
-        password: Option<String>,
-    },
     /// Report the divergence between agent `agent`'s local applied config
     /// checkout and its forge `agent-configs/<agent>` `main`. The daemon
     /// fetches forge `main` read-only and returns a human-readable report