feat(npa): add Undebited Interest Recovery Report, fix note text width

Adds a 10th NPA report tracking memorandum "undebited interest" per IRAC
norms (accrued vs cash-recovered vs balance), wired into Export to Excel
and the NPA mega-menu. Also fixes a narrow-width text wrap on the report's
description note (new .npa-report-note class overriding pg-sub's 560px cap).

src/app/npa/npa-data.ts

@@ -553,14 +553,23 @@ export function provisionHeld(a: LoanAccount): number {
   return Math.min(a.outstandingBalance, round(provisionRequired(a) * a.provisionCoverageRatio));
 }
 
-/** Interest income de-recognised because the account has been NPA for longer than 90 days. */
-export function interestReversed(a: LoanAccount): number {
-  const stage = currentStage(a);
-  if (!isNpaStage(stage)) {
+/** Days elapsed since the account first crossed 90 days overdue (i.e. became NPA) — 0 for any
+ *  account that isn't currently NPA. The single source both interest-reversal and NPA-since-date
+ *  are built from, so neither can ever quietly drift out of step with the other. */
+export function daysSinceNpa(a: LoanAccount): number {
+  if (!isNpaStage(currentStage(a))) {
     return 0;
   }
-  const daysSinceNpa = Math.max(0, a.overdueDays - 90);
-  return round(a.outstandingBalance * (a.interestRate / 100) * (daysSinceNpa / 365));
+  return Math.max(0, a.overdueDays - 90);
+}
+
+/** Interest income de-recognised because the account has been NPA for longer than 90 days. */
+export function interestReversed(a: LoanAccount): number {
+  const days = daysSinceNpa(a);
+  if (days <= 0) {
+    return 0;
+  }
+  return round(a.outstandingBalance * (a.interestRate / 100) * (days / 365));
 }
 
 /** Date the account first crossed 90 days overdue (i.e. became NPA) — derived from overdueDays,
@@ -569,14 +578,30 @@ export function npaSinceDate(a: LoanAccount): string {
   if (!isNpaStage(currentStage(a))) {
     return '—';
   }
-  const daysSinceNpa = Math.max(0, a.overdueDays - 90);
-  return fmt(addDays(new Date(), -daysSinceNpa));
+  return fmt(addDays(new Date(), -daysSinceNpa(a)));
 }
 
 export function totalRecovered(a: LoanAccount): number {
   return a.recoveries.reduce((s, r) => s + r.amount, 0);
 }
 
+/**
+ * Cash recovered against an NPA account is appropriated to the memorandum "undebited interest"
+ * bucket first — consistent with IRAC norms recognising NPA interest income only on actual cash
+ * receipt, never on accrual — and only the balance beyond that reduces principal. Capped at the
+ * interest actually accrued, so this can never show more interest "recovered" than ever accrued.
+ */
+export function interestRecoveredCash(a: LoanAccount): number {
+  return Math.min(totalRecovered(a), interestReversed(a));
+}
+
+/** Memorandum interest still un-recovered — the "undebited interest" carried outside the
+ *  borrower's loan account (per IRAC norms), less whatever cash has actually been appropriated
+ *  against it so far. */
+export function undebitedInterestBalance(a: LoanAccount): number {
+  return interestReversed(a) - interestRecoveredCash(a);
+}
+
 export function movementLabel(prev: NpaStage, curr: NpaStage): string {
   if (prev === curr) {
     return 'No Change';
@@ -608,6 +633,7 @@ export const REPORT_META: ReportMeta[] = [
   { id: 'account-detail', group: 'analysis', label: 'NPA Account Detail Report' },
   { id: 'movement', group: 'analysis', label: 'NPA Movement Report' },
   { id: 'provision', group: 'analysis', label: 'NPA with Provision and Required Provision' },
+  { id: 'undebited-interest', group: 'analysis', label: 'Undebited Interest Recovery Report' },
   { id: 'probable', group: 'classification', label: 'Probable NPA' },
   { id: 'sma', group: 'classification', label: 'SMA Report' }
 ];