feat(clients): maker-checker for client edits (frontend)

- New "Pending Client Edits" screen under Checker Inbox & Tasks: server-driven pagination,
  date range + Today/Yesterday/All presets, status filter (Pending/Approved/Rejected), search —
  mirrors ChequebookRequestsComponent's architecture.
- Compare dialog diffs the maker's proposed values against a point-in-time "before" snapshot
  (client-edit-diff.util.ts) captured when the edit page was opened, so only genuinely changed
  fields show — works correctly for Pending, Approved, and Rejected edits alike, since it no
  longer depends on comparing against the live (possibly already-updated) client record.
- edit-client.component.ts: General tab save now submits for approval instead of applying
  immediately, shows a pending-approval banner, and blocks a second submission while one's
  outstanding.
- error-handler.interceptor.ts: added the new /clients/{id}/edit/pending check to the existing
  "expected 403/404, don't alert" allowlist (same pattern already used for client images/KYC).

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

src/app/clients/clients.service.ts

@@ -82,6 +82,43 @@ export class ClientsService {
     return this.http.delete(`/clients/${clientId}`);
   }
 
+  /**
+   * Maker-checker for Client edits — stages the change in m_client_pending_edit instead of
+   * applying it immediately; a different user must call approveClientEdit() before it takes
+   * effect. See ClientEditApiResource on the backend.
+   */
+  submitClientEdit(clientId: string, client: any) {
+    return this.http.post(`/clients/${clientId}/edit`, client);
+  }
+
+  getPendingClientEdit(clientId: string) {
+    return this.http.get(`/clients/${clientId}/edit/pending`);
+  }
+
+  getAllPendingClientEdits(
+    status?: string,
+    clientName?: string,
+    fromDate?: string,
+    toDate?: string,
+    offset = 0,
+    limit = 20
+  ): Observable<any> {
+    let params = new HttpParams().set('offset', offset).set('limit', limit);
+    if (status) params = params.set('status', status);
+    if (clientName) params = params.set('clientName', clientName);
+    if (fromDate) params = params.set('fromDate', fromDate);
+    if (toDate) params = params.set('toDate', toDate);
+    return this.http.get(`/clients/edit/pending`, { params });
+  }
+
+  approveClientEdit(clientId: string) {
+    return this.http.post(`/clients/${clientId}/edit/approve`, {});
+  }
+
+  rejectClientEdit(clientId: string, rejectReason?: string) {
+    return this.http.post(`/clients/${clientId}/edit/reject`, { rejectReason: rejectReason || '' });
+  }
+
   getClientDataAndTemplate(clientId: string) {
     const httpParams = new HttpParams().set('template', 'true').set('staffInSelectedOfficeOnly', 'true');
     return this.http.get(`/clients/${clientId}`, { params: httpParams });