feat: DSC enrollment + MFA controls, user CRUD UX, auth error hardening

- DSC module: list/enroll/revoke dialogs and dsc.service (m_bank_user_dsc API)
- Access control: DSC + MFA toggles via disable-confirm-dialog
- Two-factor auth: expanded UX (DSC + OTP flows)
- Users: create/edit form polish, success snackbar on edit, DSC widget
  retained only inside dsc/ (removed from view-user)
- Auth: X-Requested-With added globally; error handler null-safe on
  empty 500 bodies

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/app/users/dsc/revoke-dsc-dialog/revoke-dsc-dialog.component.html

@@ -0,0 +1,57 @@
+<!--
+  Copyright since 2025 Mifos Initiative
+
+  This Source Code Form is subject to the terms of the Mozilla Public
+  License, v. 2.0. If a copy of the MPL was not distributed with this
+  file, You can obtain one at http://mozilla.org/MPL/2.0/.
+-->
+
+<h2 mat-dialog-title class="revoke-title">
+  <fa-icon icon="ban" class="revoke-title__icon"></fa-icon>
+  Revoke Digital Signature
+</h2>
+
+<mat-dialog-content class="revoke-content">
+  <p class="revoke-summary">
+    You're about to revoke
+    <strong>{{ data.dsc.commonName || 'this DSC' }}</strong>
+    (serial {{ data.dsc.dscSerialNoFull || data.dsc.dscSerialNoMasked || '—' }}). This is permanent and the certificate
+    will no longer work for two-factor authentication.
+  </p>
+
+  <mat-form-field class="revoke-reason" appearance="outline">
+    <mat-label>Reason</mat-label>
+    <input
+      matInput
+      name="reason"
+      [(ngModel)]="reason"
+      [disabled]="submitting"
+      maxlength="200"
+      placeholder="e.g. token lost, employee left"
+      required
+    />
+    @if (!reason?.trim() && submitting === false) {
+      <mat-error>Reason is required</mat-error>
+    }
+  </mat-form-field>
+
+  @if (errorMessage) {
+    <div class="revoke-error">
+      <fa-icon icon="exclamation-circle"></fa-icon>
+      {{ errorMessage }}
+    </div>
+  }
+</mat-dialog-content>
+
+<mat-dialog-actions align="end" class="revoke-actions">
+  <button mat-stroked-button (click)="cancel()" type="button" [disabled]="submitting">Cancel</button>
+  <button mat-flat-button color="warn" (click)="confirm()" type="button" [disabled]="!reason?.trim() || submitting">
+    @if (submitting) {
+      <mat-spinner diameter="18"></mat-spinner>
+      <span>Revoking…</span>
+    } @else {
+      <fa-icon icon="ban"></fa-icon>
+      <span>Revoke</span>
+    }
+  </button>
+</mat-dialog-actions>

src/app/users/dsc/revoke-dsc-dialog/revoke-dsc-dialog.component.scss

@@ -0,0 +1,60 @@
+/**
+ * Copyright since 2025 Mifos Initiative
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+.revoke-title {
+  display: flex;
+  align-items: center;
+  gap: 10px;
+  color: #b91c1c;
+  margin: 0;
+
+  &__icon {
+    color: #dc2626;
+  }
+}
+
+.revoke-content {
+  padding-top: 8px;
+}
+
+.revoke-summary {
+  margin: 0 0 16px;
+  color: #334155;
+  font-size: 0.95rem;
+  line-height: 1.5;
+
+  strong {
+    color: #0f172a;
+  }
+}
+
+.revoke-reason {
+  width: 100%;
+}
+
+.revoke-error {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  margin-top: 8px;
+  padding: 10px 12px;
+  border-radius: 6px;
+  background: #fef2f2;
+  color: #b91c1c;
+  font-size: 0.88rem;
+}
+
+.revoke-actions {
+  gap: 8px;
+
+  button {
+    display: inline-flex;
+    align-items: center;
+    gap: 6px;
+  }
+}

src/app/users/dsc/revoke-dsc-dialog/revoke-dsc-dialog.component.ts

@@ -0,0 +1,80 @@
+/**
+ * Copyright since 2025 Mifos Initiative
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+import { Component, inject } from '@angular/core';
+import { FormsModule } from '@angular/forms';
+import {
+  MAT_DIALOG_DATA,
+  MatDialogRef,
+  MatDialogTitle,
+  MatDialogContent,
+  MatDialogActions
+} from '@angular/material/dialog';
+import { MatButton } from '@angular/material/button';
+import { MatFormField, MatLabel, MatError } from '@angular/material/form-field';
+import { MatInput } from '@angular/material/input';
+import { MatProgressSpinner } from '@angular/material/progress-spinner';
+import { FaIconComponent } from '@fortawesome/angular-fontawesome';
+
+import { STANDALONE_SHARED_IMPORTS } from 'app/standalone-shared.module';
+import { DscService } from '../dsc.service';
+import { BankUserDsc } from '../dsc.model';
+
+interface RevokeDialogData {
+  dsc: BankUserDsc;
+}
+
+@Component({
+  selector: 'mifosx-revoke-dsc-dialog',
+  templateUrl: './revoke-dsc-dialog.component.html',
+  styleUrls: ['./revoke-dsc-dialog.component.scss'],
+  imports: [
+    ...STANDALONE_SHARED_IMPORTS,
+    FormsModule,
+    MatDialogTitle,
+    MatDialogContent,
+    MatDialogActions,
+    MatButton,
+    MatFormField,
+    MatLabel,
+    MatError,
+    MatInput,
+    MatProgressSpinner,
+    FaIconComponent
+  ]
+})
+export class RevokeDscDialogComponent {
+  private service = inject(DscService);
+  private dialogRef = inject(MatDialogRef<RevokeDscDialogComponent>);
+  data = inject<RevokeDialogData>(MAT_DIALOG_DATA);
+
+  reason = '';
+  submitting = false;
+  errorMessage = '';
+
+  cancel(): void {
+    this.dialogRef.close({ revoked: false });
+  }
+
+  confirm(): void {
+    if (!this.reason?.trim() || !this.data?.dsc?.id) return;
+    this.submitting = true;
+    this.errorMessage = '';
+    this.service.revokeDsc(this.data.dsc.id, this.reason.trim()).subscribe({
+      next: () => {
+        this.submitting = false;
+        this.dialogRef.close({ revoked: true });
+      },
+      error: (err) => {
+        this.submitting = false;
+        this.errorMessage =
+          err?.error?.defaultUserMessage || err?.error?.message || err?.message || 'Could not revoke DSC.';
+      }
+    });
+  }
+}