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

@@ -49,6 +49,18 @@
     </div>
   }
 
+  @if (firstOpenNeedsCashMigration && !missedOnly) {
+    <div class="bd-locked">
+      <mat-icon>lock</mat-icon>
+      <span>
+        This branch has never opened a business day, and its Cash at Vault GL account has no opening balance yet. Count
+        the vault and open the first business day together from
+        <a [routerLink]="['/accounting/migrate-cash-denomination']">Migrate Cash Denomination</a> — Open Day here is
+        locked until that is done, so today's cash tracking never starts out of step with the ledger.
+      </span>
+    </div>
+  }
+
   <!-- Missed closes first: these are the ones that need action. -->
   @if (missed.length > 0) {
     <div class="db-exceptions">
@@ -703,10 +715,10 @@
                   <span class="db-muted">· {{ timeOnly(d.closedAt) }}</span>
                 }
               </td>
-              <td class="num">{{ d.closingCash != null ? '₹' + (d.closingCash | number: '1.2-2') : '—' }}</td>
-              <td class="num">{{ d.bookCash != null ? '₹' + (d.bookCash | number: '1.2-2') : '—' }}</td>
+              <td class="num">{{ hasValue(d.closingCash) ? '₹' + (d.closingCash | number: '1.2-2') : '—' }}</td>
+              <td class="num">{{ hasValue(d.bookCash) ? '₹' + (d.bookCash | number: '1.2-2') : '—' }}</td>
               <td>
-                @if (d.cashDifference == null) {
+                @if (!hasValue(d.cashDifference)) {
                   —
                 } @else if (d.cashDifference === 0) {
                   <span class="db-badge db-badge--ok">Tallied</span>