feat(bank-transfer): convert bank transfer to maker-checker approval flow

- submitBankTransfer() now calls submit() with requestType='BANK_TRANSFER'
  instead of the immediate-execution /banktransfer endpoint
- Confirm dialog updated: 'Submit for Approval' instead of 'Execute Transfer'
- disbursement-review: isBankTransferMode getter, separate DR/CR entry tables,
  'Approve Bank Transfer' button label, correct isCollectionMode guard
- Disbursement Requests checker inbox: Type badge (Bank Transfer/Collection/
  Disbursement) column, GL column shows 'Intra-bank transfer' for BT requests
- Checker inbox tab renamed to 'Disbursement & Transfers'

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

src/app/cashier/clerk-disbursement.service.ts

@@ -45,4 +45,8 @@ export class ClerkDisbursementService {
   reject(id: number, reason: string): Observable<any> {
     return this.http.post(`/clerk/disbursement-requests/${id}/reject`, { reason });
   }
+
+  bankTransfer(data: any): Observable<any> {
+    return this.http.post('/clerk/disbursement-requests/banktransfer', data);
+  }
 }