feat(search): restrict client search to INDIVIDUAL only for nominee, introducer, joint holders

- nominee-form: searchByText now passes legalFormType='INDIVIDUAL' for both
  nominee search and guardian search — prevents entities/companies appearing
- introducer-search: same INDIVIDUAL filter applied
- add-related-client-dialog: INDIVIDUAL filter for joint account holders,
  partners, and members search

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/app/current-accounts/current-account-stepper/current-account-details-step/add-related-client-dialog/add-related-client-dialog.component.ts

@@ -79,7 +79,7 @@ export class AddRelatedClientDialogComponent implements OnDestroy {
     }
     this.isSearching = true;
     this.searchTimer = setTimeout(() => {
-      this.clientsService.searchByText(value.trim(), 0, 10, '', '', true).subscribe({
+      this.clientsService.searchByText(value.trim(), 0, 10, '', '', true, 'INDIVIDUAL').subscribe({
         next: (res: any) => {
           this.searchResults = res?.content || [];
           this.isSearching = false;

src/app/shared/introducer-search/introducer-search.component.ts

@@ -59,7 +59,7 @@ export class IntroducerSearchComponent {
     }
     this.searching = true;
     this.searchTimer = setTimeout(() => {
-      this.clientsService.searchByText(text, 0, 8, '', '', true).subscribe({
+      this.clientsService.searchByText(text, 0, 8, '', '', true, 'INDIVIDUAL').subscribe({
         next: (data: any) => {
           this.searchResults = data?.content || [];
           this.searching = false;

src/app/shared/nominee-form/nominee-form.component.ts

@@ -117,7 +117,7 @@ export class NomineeFormComponent implements OnInit {
     }
     this.searching = true;
     this.searchTimer = setTimeout(() => {
-      this.clientsService.searchByText(text, 0, 8, '', '', true).subscribe({
+      this.clientsService.searchByText(text, 0, 8, '', '', true, 'INDIVIDUAL').subscribe({
         next: (data: any) => {
           this.searchResults = data?.content || [];
           this.searching = false;
@@ -248,7 +248,7 @@ export class NomineeFormComponent implements OnInit {
     }
     this.guardianSearching = true;
     this.guardianSearchTimer = setTimeout(() => {
-      this.clientsService.searchByText(text, 0, 8, '', '', true).subscribe({
+      this.clientsService.searchByText(text, 0, 8, '', '', true, 'INDIVIDUAL').subscribe({
         next: (data: any) => {
           this.guardianSearchResults = data?.content || [];
           this.guardianSearching = false;