The admin CLI moves a persona to another login and deletes a login; the deploy no longer signs in

The owner took @thepra, which the deploy had made and kept under its own login deploy-smoke for its signed-in check, for
the administrator's login (owner decision 2026-10-17). No persona could change login, so:
- admin move-persona <persona> <root> re-points the persona's link first, so the old login can no longer exchange a token
  for it, then ends its Mastodon tokens and authorizations. Its actor, posts and followers stay; nobody outside is told,
  since nothing they hold changes.
- admin delete-root <root> deletes a login as the client deletes its own (RootRemoval): every persona it still has goes
  with it, announced deleted, and its sessions end.
- admin smoke and the deploy's signed-in step are gone, since the step would make deploy-smoke again and fail to make
  @thepra under it. The deploy keeps its anonymous checks; tools/smoke/oauth.sh stays for the pasture's privapub_token.

Tests: move-persona (the persona listed under its new login only, its old token refused, unknown persona or login exit 1)
and delete-root (the login and its persona deleted, the login refused); the whole suite passes (963).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tools/pasture/lib/interop.sh

@@ -43,7 +43,7 @@ privapub_root() {
 }
 
 # privapub_token <persona>: creates the persona under the pasture root if needed and returns a Mastodon token for it,
-# through the same OAuth flow the deploy's smoke check uses (tools/smoke/oauth.sh).
+# through the real OAuth flow (tools/smoke/oauth.sh).
 privapub_token() {
 	local persona=$1 jwt
 	jwt=$(privapub_root)