feat(admin): deleted-account dossier + operator delete-user action

The user-detail console gains a Deletion & retention panel: last login (time + IP),
the tombstone (deleted-at + retained real name), and the retention journal (the legal
dossier of detached credentials). A Delete-user action runs the same deletion
orchestration as the in-app flow (mirrors the email-erase pattern). Store readers
RetainedIdentities + DeletionInfo back the view; integration test covers them.

backend/internal/server/handlers_admin_console.go

@@ -62,6 +62,7 @@ func (s *Server) registerConsole(router *gin.Engine) {
 	gm.POST("/users/:id/grant-role", s.consoleGrantRole)
 	gm.POST("/users/:id/revoke-role", s.consoleRevokeRole)
 	gm.POST("/users/:id/remove-email", s.consoleRemoveEmail)
+	gm.POST("/users/:id/delete", s.consoleDeleteUser)
 	gm.GET("/reasons", s.consoleReasons)
 	gm.POST("/reasons", s.consoleCreateReason)
 	gm.POST("/reasons/:id/update", s.consoleUpdateReason)
@@ -368,6 +369,25 @@ func (s *Server) consoleUserDetail(c *gin.Context) {
 			view.Identities = append(view.Identities, adminconsole.IdentityRow{Kind: idn.Kind, ExternalID: idn.ExternalID, Confirmed: idn.Confirmed, CreatedAt: fmtTime(idn.CreatedAt)})
 		}
 	}
+	if info, err := s.accounts.DeletionInfo(ctx, id); err == nil {
+		if info.LastLoginAt != nil {
+			view.LastLoginAt = fmtTime(*info.LastLoginAt)
+		}
+		view.LastLoginIP = info.LastLoginIP
+		if info.DeletedAt != nil {
+			view.Deleted = true
+			view.DeletedAt = fmtTime(*info.DeletedAt)
+			view.DeletedName = info.DeletedDisplayName
+		}
+	}
+	if rets, err := s.accounts.RetainedIdentities(ctx, id); err == nil {
+		for _, r := range rets {
+			view.Retained = append(view.Retained, adminconsole.RetainedRow{
+				Kind: r.Kind, ExternalID: r.ExternalID, Reason: r.Reason,
+				Confirmed: r.Confirmed, LinkedAt: fmtTime(r.LinkedAt), DetachedAt: fmtTime(r.DetachedAt),
+			})
+		}
+	}
 	if tg, err := s.accounts.IdentityExternalID(ctx, id, account.KindTelegram); err == nil {
 		view.TelegramID = tg
 	}
@@ -979,6 +999,22 @@ func (s *Server) consoleRemoveEmail(c *gin.Context) {
 	}
 }
 
+// consoleDeleteUser deletes an account from the console — the operator-initiated equivalent
+// of the in-app deletion (legal retention, not erasure): the account is tombstoned, its
+// credentials journalled + freed, its live surfaces anonymised, and its sessions revoked.
+func (s *Server) consoleDeleteUser(c *gin.Context) {
+	id, ok := s.consoleUUID(c, "/_gm/users")
+	if !ok {
+		return
+	}
+	back := "/_gm/users/" + id.String()
+	if err := s.deleteAccount(c.Request.Context(), id); err != nil {
+		s.consoleError(c, err)
+		return
+	}
+	s.renderConsoleMessage(c, "Deleted", "the account was deleted: its credentials were journalled and freed, its data anonymised, and its sessions revoked", back)
+}
+
 // consoleBlockUser manually blocks an account: it records the suspension (permanent or until a
 // parsed deadline, snapshotting the chosen reason's en/ru text) and forfeits the player's active
 // games, removing them from matchmaking. The block takes effect on the player's next request.