fix: tenant-config fixes, cashier/share/savings UI bugs, and menu-access hardcoding

- Add Balance Sheet report and disabled-features accounting config
- Point menu-access tenant header and env.js/environment.ts tenant identifier
  at env config instead of hardcoded 'default'/'lincpay' literals
- Surface the real backend error (not a generic "no reference id") when an
  OTP send fails in contact-otp-block
- Fix branch-day "₹null" display bug (null vs undefined) and add a guard
  blocking a branch's first-ever day open before cash denomination migration
- Dynamically size the denomination count input and block re-opening an
  already-open business day from Migrate Cash Denomination
- Lock the denomination-managed cash GL row in Migrate Opening Balances
  (read-only, with a link back to Migrate Cash Denomination)
- Remove duplicate Cancel/Submit action bars on the Share Product and
  Savings Account creation preview steps; align Previous into the same row
- Hide "Apply Collection" on a share account once its advance collection
  is already settled (further purchases go through Apply Additional Shares)

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/app/accounting/accounting.service.ts

@@ -116,6 +116,22 @@ export class AccountingService {
     return this.http.get(`/glaccounts`, { params: httpParams });
   }
 
+  /**
+   * As-on-date balance sheet, grouped by Header/Detail hierarchy — see BalanceSheetApiResource.
+   * @param asOnDate yyyy-MM-dd. Defaults to today on the backend when omitted.
+   * @param officeId Optional — scopes every balance to one office instead of the whole organization.
+   */
+  getBalanceSheet(asOnDate?: string, officeId?: number): Observable<any> {
+    let httpParams = new HttpParams();
+    if (asOnDate) {
+      httpParams = httpParams.set('asOnDate', asOnDate);
+    }
+    if (officeId != null) {
+      httpParams = httpParams.set('officeId', officeId.toString());
+    }
+    return this.http.get('/accounting/balancesheet', { params: httpParams });
+  }
+
   /**
    * @param transactionId Transaction ID of journal entries.
    * @returns {Observable<any>} Journal Entries.