feat: New change password page with server capabilities check

lib/pages/settings_security/settings_security.dart

@@ -23,42 +23,6 @@ class SettingsSecurity extends StatefulWidget {
 }
 
 class SettingsSecurityController extends State<SettingsSecurity> {
-  void changePasswordAccountAction() async {
-    final input = await showTextInputDialog(
-      useRootNavigator: false,
-      context: context,
-      title: L10n.of(context)!.changePassword,
-      okLabel: L10n.of(context)!.ok,
-      cancelLabel: L10n.of(context)!.cancel,
-      textFields: [
-        DialogTextField(
-          hintText: L10n.of(context)!.chooseAStrongPassword,
-          obscureText: true,
-          minLines: 1,
-          maxLines: 1,
-        ),
-        DialogTextField(
-          hintText: L10n.of(context)!.repeatPassword,
-          obscureText: true,
-          minLines: 1,
-          maxLines: 1,
-        ),
-      ],
-    );
-    if (input == null) return;
-    final success = await showFutureLoadingDialog(
-      context: context,
-      future: () => Matrix.of(context)
-          .client
-          .changePassword(input.last, oldPassword: input.first),
-    );
-    if (success.error == null) {
-      ScaffoldMessenger.of(context).showSnackBar(
-        SnackBar(content: Text(L10n.of(context)!.passwordHasBeenChanged)),
-      );
-    }
-  }
-
   void setAppLockAction() async {
     if (AppLock.of(context).isActive) {
       AppLock.of(context).showLockScreen();