feat(rbi-reserve,savings): Form 1/Form 9 returns UI, branch-wise interest posting reports and summary

- Reports > Interest Posting Reports: per branch and product, generate/regenerate
  at any time, approve; branch column, HO-on-behalf marker, posted txn per account
- Reports > Interest Posting Summary (branch-wise) for the head office, with Excel export
- Day Close warns and disables Close Day while the branch's interest report is unapproved
- Savings product accounting: Interest On Savings (expense), Savings Interest Payable
  and Paid (liability rows, required)
- RBI Form 1 statutory and Form 9 return screens, reserve config updates
- Interest posting report GETs exempted from the response cache

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

src/app/cashier/branch-day/branch-day.component.html

@@ -107,11 +107,26 @@
         </span>
       </div>
       @if (canOperate) {
-        <button type="button" class="pg-btn pg-btn--primary" (click)="startClose(openDay)">
+        <button
+          type="button"
+          class="pg-btn pg-btn--primary"
+          (click)="startClose(openDay)"
+          [disabled]="interestPending.length > 0"
+        >
           <mat-icon>lock</mat-icon> Close Day
         </button>
       }
     </div>
+    @if (interestPending.length > 0) {
+      <div class="bd-interest-alert">
+        <mat-icon>warning</mat-icon>
+        <span>
+          Savings interest posting report is not approved for <strong>{{ interestPending.join(', ') }}</strong
+          >. Approve it in <a routerLink="/reports/interest-posting">Reports → Interest Posting Reports</a> before
+          closing the day.
+        </span>
+      </div>
+    }
   } @else if (loaded && canOperate) {
     <div class="bd-current bd-current--shut">
       <div class="bd-current__main">

src/app/cashier/branch-day/branch-day.component.scss

@@ -372,3 +372,30 @@
     color: #d97706;
   }
 }
+
+// Shown under the open day while a savings interest posting report due today is unapproved.
+.bd-interest-alert {
+  display: flex;
+  align-items: flex-start;
+  gap: 8px;
+  margin: 8px 0 12px;
+  padding: 10px 14px;
+  border: 1px solid #f59e0b;
+  border-radius: 8px;
+  background: #fef3c7;
+  color: #92400e;
+  font-size: 13px;
+
+  mat-icon {
+    flex-shrink: 0;
+    font-size: 20px;
+    width: 20px;
+    height: 20px;
+  }
+
+  a {
+    color: inherit;
+    font-weight: 600;
+    text-decoration: underline;
+  }
+}

src/app/cashier/branch-day/branch-day.component.ts

@@ -189,6 +189,23 @@ export class BranchDayComponent implements OnInit {
     return this.totalOf(this.closeCounts);
   }
 
+  /**
+   * Savings products whose interest posting report is due today and not yet approved. The close is
+   * refused by the backend while any is pending; this only says so before the user tries.
+   */
+  interestPending: string[] = [];
+
+  private checkInterestReports(): void {
+    if (!this.openDay?.businessDate) {
+      this.interestPending = [];
+      return;
+    }
+    this.service
+      .interestDayCloseCheck(this.openDay.businessDate, this.openDay.officeId)
+      .pipe(catchError(() => of(null)))
+      .subscribe((res) => (this.interestPending = res?.pendingProducts ?? []));
+  }
+
   load(): void {
     this.loading = true;
     this.errorMsg = '';
@@ -210,6 +227,7 @@ export class BranchDayComponent implements OnInit {
         this.canOperate = !!res?.canOperate;
         this.openDate = this.today;
         this.checkFirstOpenCashMigration();
+        this.checkInterestReports();
       });
 
     this.service

src/app/cashier/cashier.service.ts

@@ -205,6 +205,23 @@ export class CashierService {
     return this.http.get('/branchday', { params });
   }
 
+  /**
+   * The savings products whose interest posting report is due for the date and not yet approved —
+   * the backend refuses to close any branch's day while one is pending.
+   */
+  interestDayCloseCheck(
+    date?: string,
+    officeId?: number
+  ): Observable<{ businessDate: string; canClose: boolean; pendingProducts: string[] }> {
+    let params = new HttpParams();
+    if (date) params = params.set('date', date);
+    if (officeId) params = params.set('officeId', String(officeId));
+    return this.http.get<{ businessDate: string; canClose: boolean; pendingProducts: string[] }>(
+      '/savingsinterestpostingreports/day-close-check',
+      { params }
+    );
+  }
+
   /** Days opened and never closed — today's own open day excluded. */
   branchDayMissed(officeId?: number): Observable<any> {
     let params = new HttpParams();