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/rbi-circulars/rbi-circulars.service.ts

@@ -71,11 +71,17 @@ export class RbiCircularsService {
    * @param reportingDate yyyy-MM-dd. Defaults to the current business date on the backend.
    * @param officeId Optional — scopes every figure to one office.
    */
-  getForm1(reportingDate?: string, officeId?: number): Observable<any> {
+  getForm1(reportingDate?: string, baseDate?: string, officeId?: number): Observable<any> {
     let params = new HttpParams();
     if (reportingDate) {
       params = params.set('reportingDate', reportingDate);
     }
+    // The base date can be given outright. The 45-day lag lands where it lands, and a bank reading
+    // an earlier fortnight — or correcting a filing — needs to name the date the base is struck at
+    // rather than work backwards from it. Left blank it is derived from the lag as before.
+    if (baseDate) {
+      params = params.set('baseDate', baseDate);
+    }
     if (officeId != null) {
       params = params.set('officeId', String(officeId));
     }
@@ -97,6 +103,44 @@ export class RbiCircularsService {
     return this.http.get('/rbireservereturn/form9', { params });
   }
 
+  /**
+   * Form 9 in the shape it is filed — the statutory statement of compliance with section 24.
+   *
+   * A different statement from `getForm9`, not a reformatting: three dated columns rather than one,
+   * and the ratio charged on the last Friday of the second preceding fortnight rather than on the
+   * month end itself.
+   */
+  getForm9Statutory(reportingDate?: string, officeId?: number): Observable<any> {
+    let params = new HttpParams();
+    if (reportingDate) {
+      params = params.set('reportingDate', reportingDate);
+    }
+    if (officeId != null) {
+      params = params.set('officeId', String(officeId));
+    }
+    return this.http.get('/rbireservereturn/form9-statutory', { params });
+  }
+
+  /**
+   * Form IX — the Return on Assets and Liabilities a co-operative bank files monthly, code R408.
+   *
+   * A different return from `getForm9` despite the name: that one reports the SLR ratio, this one
+   * reports the whole balance sheet. Every figure comes back in rupees thousands, with the rupee
+   * figure alongside it so a line can still be reconciled against the ledger.
+   *
+   * @param reportingDate yyyy-MM-dd — any date in the month; the return reports that month's end.
+   */
+  getForm9Return(reportingDate?: string, officeId?: number): Observable<any> {
+    let params = new HttpParams();
+    if (reportingDate) {
+      params = params.set('reportingDate', reportingDate);
+    }
+    if (officeId != null) {
+      params = params.set('officeId', String(officeId));
+    }
+    return this.http.get('/rbireservereturn/form9-return', { params });
+  }
+
   /**
    * OSS 1 — Return on Assets and Liabilities, computed live from the ledger.
    *
@@ -121,6 +165,39 @@ export class RbiCircularsService {
     return this.http.get('/ossreturn/oss2', { params: this.ossParams(quarterEndDate, officeId) });
   }
 
+  /**
+   * Form 1 as a co-operative bank files it — Banking Regulation (Co-operative Societies) Rules
+   * 1966, Rule 5, sections 18(1) and 24(3).
+   *
+   * A different statement from `getForm1`, not a reformatting: three columns rather than one, both
+   * ratios settled on the same liabilities, and those liabilities taken from the last Friday of the
+   * second preceding fortnight rather than a 45-day lag.
+   */
+  getForm1Statutory(
+    reportingDate?: string,
+    firstColumnDate?: string,
+    secondColumnDate?: string,
+    officeId?: number
+  ): Observable<any> {
+    let params = new HttpParams();
+    if (reportingDate) {
+      params = params.set('reportingDate', reportingDate);
+    }
+    // Both fortnight closes can be given outright. A bank filing August wants 15/08 and 31/08 on
+    // the face of the form whatever today is, and one date cannot produce a pair that spans a month
+    // boundary or skips a fortnight — which a late or corrected filing needs.
+    if (firstColumnDate) {
+      params = params.set('firstColumnDate', firstColumnDate);
+    }
+    if (secondColumnDate) {
+      params = params.set('secondColumnDate', secondColumnDate);
+    }
+    if (officeId != null) {
+      params = params.set('officeId', String(officeId));
+    }
+    return this.http.get('/rbireservereturn/form1-statutory', { params });
+  }
+
   // ── Saved returns ──
 
   /**