feat(clients): dual-OTP contact-change verification, webcam signature capture, and client history tab

Frontend counterpart to the backend dual-OTP contact-change feature:

- New ContactOtpBlockComponent (6-box segmented OTP input) used up to 4x in
  Edit Client (old/new mobile, old/new email — grouped under per-field
  sub-headers) and once each for mobile/email in Create Client, gating
  Save/Save & Next until every required box is verified.
- edit-client.component.ts: detects mobile/email/DOB changes against the
  loaded snapshot using local-date comparison (not `.toISOString()`, which
  false-triggers a day-shift in positive-UTC-offset timezones) and
  trimmed/case-insensitive email comparison (autofill whitespace or re-typed
  casing no longer reads as a change the masked preview can't explain).
- client-kyc-step.component.ts: new `invalidFieldLabels` getter names every
  currently-invalid required KYC field, surfaced via the Save & Next tooltip
  in both create-client and edit-client so a greyed-out button always
  explains what's still missing instead of a generic message.
- CaptureImageDialogComponent generalized for both profile photo and
  signature (photograph-a-paper-signature) capture:
  - Frame aspect now matches the requested getUserMedia resolution
    (4:3 profile / 16:9 signature) with object-fit: cover, eliminating the
    pillarboxing (black bars) a mismatched box previously caused.
  - Suppresses Chromium's auto-injected PiP/cast corner overlay icons.
  - Frame height capped in vh (not just px) so the dialog fits short
    viewports instead of pushing Cancel/Upload below the fold.
- upload-document-dialog.component.ts: generic Documents-tab upload now also
  offers "Capture from Webcam" alongside Browse, reusing the same capture
  dialog.
- New client History tab (reuses the existing Audit Trail data, scoped to
  this client) and dataUrlToFile/dataUrlToBlob util for routing webcam
  captures through the same upload pipelines as a picked file.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/app/shared/icons.module.ts

@@ -166,6 +166,7 @@ import {
   faClipboardList,
   faMap,
   faCamera,
+  faVideo,
   faSlidersH,
   faPrint,
   faCertificate,
@@ -401,6 +402,7 @@ export class IconsModule {
       faClipboardList,
       faMap,
       faCamera,
+      faVideo,
       faSlidersH,
       faPrint,
       faCertificate,

src/app/shared/utils/data-url.util.ts

@@ -0,0 +1,36 @@
+/**
+ * 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/.
+ */
+
+/**
+ * Converts a `data:` URL (e.g. produced by `HTMLCanvasElement.toDataURL()` in the
+ * webcam-capture dialog) into a Blob, preserving the embedded MIME type.
+ */
+export function dataUrlToBlob(dataUrl: string): Blob {
+  const [
+    header,
+    base64
+  ] = dataUrl.split(',');
+  const mimeMatch = /data:(.*?);base64/.exec(header || '');
+  const mime = mimeMatch ? mimeMatch[1] : 'image/jpeg';
+  const binary = atob(base64 || '');
+  const bytes = new Uint8Array(binary.length);
+  for (let i = 0; i < binary.length; i++) {
+    bytes[i] = binary.charCodeAt(i);
+  }
+  return new Blob([bytes], { type: mime });
+}
+
+/**
+ * Converts a `data:` URL into a `File` so it can be routed through the same
+ * upload/crop pipelines used for file-picker input (multipart form posts, the
+ * image-crop dialog, etc).
+ */
+export function dataUrlToFile(dataUrl: string, filename: string): File {
+  const blob = dataUrlToBlob(dataUrl);
+  return new File([blob], filename, { type: blob.type || 'image/jpeg' });
+}