DEV: update rake task to disable 2FA for a user (#29052)

- limits security key deletes to second factor keys
- also deletes backup codes (lingering backup codes break login flow entirely)

* Add spec for rake task to disable 2FA for a user

spec/tasks/users_spec.rb

@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+RSpec.describe "tasks/users" do
+  before do
+    Rake::Task.clear
+    Discourse::Application.load_tasks
+  end
+
+  describe "users:disable_2fa" do
+    let(:user) { Fabricate(:user) }
+
+    it "should remove all 2fa methods for user with given username" do
+      Fabricate(:user_second_factor_totp, user: user, name: "TOTP", enabled: true)
+      Fabricate(:user_second_factor_totp, user: user, name: "TOTP2", enabled: true)
+      Fabricate(
+        :user_security_key_with_random_credential,
+        user: user,
+        name: "YubiKey",
+        enabled: true,
+      )
+      Fabricate(:passkey_with_random_credential, user: user) # This should not be removed
+
+      backup_codes = user.generate_backup_codes
+
+      expect(backup_codes.length).to be 10
+      expect(user.user_second_factors.backup_codes).to be_present
+      expect(user.user_second_factors.totps.count).to eq(2)
+      expect(user.second_factor_security_keys.count).to eq(1)
+
+      stdout = capture_stdout { Rake::Task["users:disable_2fa"].invoke(user.username) }
+      user.reload
+
+      expect(stdout.chomp).to eq("2FA disabled for #{user.username}")
+      expect(user.user_second_factors.totps.count).to eq(0)
+      expect(user.second_factor_security_keys.count).to eq(0)
+      expect(user.user_second_factors.backup_codes.count).to eq(0)
+      expect(user.passkey_credential_ids.count).to eq(1)
+    end
+  end
+end