feat(cashier): cashier-only cash operations, exchange PAN/denomination checks and Branch Cash Position

- Cash Exchange Entry: customer details with PAN (mandatory above Rs 50,000), cashier card,
  denomination-wise validation against the master and real-time impact preview.
- Inter-Cashier Transfer: sender fixed to the logged-in cashier, both sides' details and
  denomination holdings shown, blocked until both are allocated cash.
- Reconciliation, exchange and inter-cashier operate on the logged-in cashier only.
- New Branch Cash Position screen (vault + cashier drawers, denomination-wise).
- Customer search dialog shows the KYC PAN.
- Cashier menu cleanup: Excess/Closing report and Exchange Detail removed, nav compacted to one row.
- Reverse actions removed from cash transfer, settlement, exchange and inter-cashier.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/app/cashier/cash-history/cash-history.component.scss

@@ -47,38 +47,6 @@
   }
 }
 
-.reverse-panel {
-  display: flex;
-  align-items: center;
-  gap: 12px;
-  padding: 12px 16px;
-  background: #fffbeb;
-  border: 1px solid #fcd34d;
-  border-radius: 10px;
-  flex-wrap: wrap;
-  font-size: 13px;
-  color: #92400e;
-
-  .reverse-icon {
-    color: #f59e0b;
-    font-size: 20px;
-    height: 20px;
-    width: 20px;
-  }
-
-  .reverse-reason {
-    flex: 1 1 200px;
-    height: 34px;
-    padding: 0 10px;
-    border: 1px solid #fcd34d;
-    border-radius: 7px;
-    font-size: 13px;
-    font-family: inherit;
-    background: #fff;
-    color: #1a1a1a;
-  }
-}
-
 /* ── Action buttons cell ── */
 .action-btns {
   display: flex;