feat(cashier): denomination overdraft validation, exchange detail fix, cash exchange in reports

- Savings/Current/FD/RD withdrawal forms: card-style overdraft warning when
  requested denomination count exceeds cashier stock; submit blocked on overdraft
- Cash History detail view: show both RECEIVED and GIVEN denomination breakdowns
  for Cash Exchange (previously only RECEIVED side was displayed)
- Closing Cash Report: add Cash Exchanges section (denomination-wise received/given/net)
- Excess Transaction Report: include cash exchanges >= threshold with Type badge
  (Exchange/Txn) and ID Proof column for RBI/AML compliance
- cashier-shared.scss: etr-badge and closing-exchange-head styles
- Cash Exchange entry: overdraft warning redesigned to cx-overdraft-card BEM layout

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

src/app/cashier/cash-exchange-entry/cash-exchange-entry.component.scss

@@ -73,6 +73,208 @@
   }
 }
 
+/* ── Customer info bar ── */
+.cx-customer-bar {
+  display: flex;
+  align-items: center;
+  gap: 12px;
+  padding: 10px 14px;
+  background: #f8fafc;
+  border: 1px solid #e2e8f0;
+  border-radius: 10px;
+  flex-wrap: wrap;
+}
+
+.cx-customer-toggle {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  font-size: 13px;
+  font-weight: 600;
+  color: #475569;
+  cursor: pointer;
+  user-select: none;
+
+  mat-icon {
+    font-size: 20px;
+    height: 20px;
+    width: 20px;
+    color: #94a3b8;
+  }
+
+  &--active {
+    color: #1e40af;
+
+    mat-icon {
+      color: #1e40af;
+    }
+  }
+}
+
+.cx-walk-in {
+  display: flex;
+  align-items: center;
+  gap: 4px;
+  font-size: 12px;
+  color: #64748b;
+
+  mat-icon {
+    font-size: 16px;
+    height: 16px;
+    width: 16px;
+  }
+}
+
+.cx-pan-required {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  padding: 4px 10px;
+  background: #fffbeb;
+  border: 1px solid #fcd34d;
+  border-radius: 6px;
+  font-size: 12px;
+  font-weight: 600;
+  color: #92400e;
+
+  mat-icon {
+    font-size: 16px;
+    height: 16px;
+    width: 16px;
+    color: #d97706;
+  }
+}
+
+.cx-field--inline {
+  flex-direction: row;
+  align-items: center;
+  gap: 8px;
+
+  span {
+    white-space: nowrap;
+  }
+
+  input {
+    width: 180px;
+  }
+}
+
+.cx-field--pan input {
+  width: 160px;
+  border-color: #fcd34d;
+
+  &:focus {
+    outline: none;
+    border-color: #d97706;
+  }
+}
+
+.cx-warn--pan {
+  background: #eff6ff;
+  border-color: #bfdbfe;
+  color: #1e40af;
+
+  mat-icon {
+    color: #2563eb;
+  }
+}
+
+.cx-overdraft-card {
+  background: #fff5f5;
+  border: 1.5px solid #fca5a5;
+  border-left: 4px solid #ef4444;
+  border-radius: 10px;
+  overflow: hidden;
+
+  &__title {
+    display: flex;
+    align-items: center;
+    gap: 8px;
+    padding: 9px 14px;
+    font-size: 13px;
+    font-weight: 700;
+    color: #7f1d1d;
+    background: #fef2f2;
+    border-bottom: 1px solid #fecaca;
+  }
+
+  &__ico {
+    color: #ef4444;
+    font-size: 18px;
+    height: 18px;
+    width: 18px;
+    flex-shrink: 0;
+  }
+
+  &__rows {
+    display: flex;
+    flex-direction: column;
+    padding: 4px 0;
+  }
+
+  &__row {
+    display: flex;
+    align-items: center;
+    gap: 10px;
+    padding: 7px 14px;
+    font-size: 12.5px;
+    color: #7f1d1d;
+
+    &:not(:last-child) {
+      border-bottom: 1px dashed #fecaca;
+    }
+  }
+
+  &__chip {
+    display: inline-flex;
+    align-items: center;
+    justify-content: center;
+    padding: 3px 10px;
+    background: linear-gradient(135deg, #fee2e2, #fecaca);
+    border: 1px solid #fca5a5;
+    border-radius: 6px;
+    font-size: 12px;
+    font-weight: 800;
+    color: #991b1b;
+    min-width: 52px;
+    letter-spacing: 0.01em;
+  }
+
+  &__stat {
+    display: flex;
+    align-items: center;
+    gap: 4px;
+
+    strong {
+      font-weight: 800;
+      font-variant-numeric: tabular-nums;
+    }
+  }
+
+  &__lbl {
+    font-size: 11px;
+    color: #b91c1c;
+    font-weight: 600;
+  }
+
+  &__dot {
+    color: #fca5a5;
+    font-weight: 700;
+    font-size: 14px;
+  }
+
+  &__short {
+    margin-left: auto;
+    padding: 2px 9px;
+    background: #fff;
+    border: 1.5px solid #f87171;
+    border-radius: 999px;
+    font-size: 11px;
+    font-weight: 800;
+    color: #b91c1c;
+  }
+}
+
 .cx-cols {
   display: grid;
   grid-template-columns: 1fr 1fr;