fix(auth): an account with a password deletes itself only with it and a code

A session alone deleted any account, with everything encrypted under its
keys (the second reading's lows; decided by the developer: the password
and a code, as a change of password takes). account.delete now takes a
DeletionProof (the password's SRP proof for a beginChange challenge, a
TOTP or recovery code, the host the device addressed); the register
checks it (requireOwnerToDelete), a member passing it on bound to its own
host. Accounts without a password, anonymous ones among them, delete with
their session as before. In the app, deleting an account with a password
asks for it and a code in a sheet of its own; a wrong one deletes
nothing.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

packages/halkyon_app/lib/l10n/halkyon_app_localizations.dart

@@ -1362,6 +1362,12 @@ abstract class HalkyonAppLocalizations {
   /// In en, this message translates to:
   /// **'Too many wrong codes in a row: no code is taken until {date}. If they weren\'t yours, someone knows your password: change it then.'**
   String passwordCodesWait(String date);
+
+  /// No description provided for @passwordDeleteIntro.
+  ///
+  /// In en, this message translates to:
+  /// **'Your account goes with everything in it, in every service of this instance. To confirm, type your password and a code from your authenticator app.'**
+  String get passwordDeleteIntro;
 }
 
 class _HalkyonAppLocalizationsDelegate