feat(fd): add Renewal Grace Period (Days) field to FD product Terms step

Frontend half of the new per-product grace-period field: number input alongside the existing
term fields, and stops forcing real default values (1 / the first period-frequency option) onto
minDepositTerm/minDepositTermTypeId, two hidden fields nobody actually edits through this form
-- left blank like their max-/in-multiples-of- siblings already correctly were, so a governed
product edit's "Proposed changes" diff no longer showed these as changed on every unrelated edit.

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

src/app/products/fixed-deposit-products/fixed-deposit-product-stepper/fixed-deposit-product-terms-step/fixed-deposit-product-terms-step.component.html

@@ -34,6 +34,35 @@
     </div>
   </div>
 
+  <!-- Renewal -->
+  <div class="fdpt-section">
+    <div class="fdpt-section__header">
+      <span class="fdpt-section__badge"><i class="fas fa-sync-alt"></i></span>
+      <span>Renewal</span>
+    </div>
+    <div class="fdpt-body">
+      <div class="fdpt-banner">
+        <span class="fdpt-banner__icon">ℹ️</span>
+        <span>
+          Leave blank for an FD on this product to keep renewing instantly, the same night it matures, as before. Set a
+          number of days and a matured "auto renew" FD instead waits on the FD Dashboard for that many days for staff to
+          renew it manually -- backdated to the original maturity date within that window, or from the day it is
+          actually renewed (with gap-period interest at the linked Savings account's rate) once the window has passed.
+        </span>
+      </div>
+      <div class="fdpt-grid fdpt-grid--three">
+        <mat-form-field appearance="outline" class="fdpt-field">
+          <mat-label>Renewal Grace Period</mat-label>
+          <input type="number" matInput formControlName="renewalGracePeriodDays" min="0" />
+          <mat-hint>Days</mat-hint>
+          @if (fixedDepositProductTermsForm.get('renewalGracePeriodDays').hasError('min')) {
+            <mat-error>Renewal Grace Period must be zero or greater</mat-error>
+          }
+        </mat-form-field>
+      </div>
+    </div>
+  </div>
+
   <!-- Interest Rate & Posting Terms -->
   <div class="fdpt-section">
     <div class="fdpt-section__header">

src/app/products/fixed-deposit-products/fixed-deposit-product-stepper/fixed-deposit-product-terms-step/fixed-deposit-product-terms-step.component.ts

@@ -74,7 +74,6 @@ export class FixedDepositProductTermsStepComponent implements OnInit, OnChanges
     this.periodFrequencyData = this.fixedDepositProductsTemplate.periodFrequencyTypeOptions || [];
 
     const isEditing = !!this.fixedDepositProductsTemplate.id;
-    const defaultPeriodTypeId = this.periodFrequencyData[0]?.id ?? null;
     const defaultAveragePeriod = this.averagePeriodData[0]?.value || 'Monthly';
     const savedEnumTypeId =
       this.fixedDepositProductsTemplate.interestCalculationType?.id || this.interestCalculationTypeData?.[0]?.id || 1;
@@ -85,12 +84,17 @@ export class FixedDepositProductTermsStepComponent implements OnInit, OnChanges
       : (this.interestCalculationTypeOptionData?.[0]?.id ?? null);
 
     this.fixedDepositProductTermsForm.patchValue({
-      minDepositTerm: this.fixedDepositProductsTemplate.minDepositTerm ?? 1,
-      minDepositTermTypeId: this.fixedDepositProductsTemplate.minDepositTermType?.id ?? defaultPeriodTypeId,
+      // Hidden, unedited-by-anyone fields -- left blank (like their max-/in-multiples-of- siblings
+      // already correctly are) rather than forced to a real default, or every single product edit
+      // submitted a "real" value against a product that had none, and a checker's "Proposed changes"
+      // review showed these two as "changed" on every unrelated edit, never anything a maker touched.
+      minDepositTerm: this.fixedDepositProductsTemplate.minDepositTerm ?? '',
+      minDepositTermTypeId: this.fixedDepositProductsTemplate.minDepositTermType?.id ?? '',
       maxDepositTerm: this.fixedDepositProductsTemplate.maxDepositTerm ?? '',
       maxDepositTermTypeId: this.fixedDepositProductsTemplate.maxDepositTermType?.id ?? '',
       inMultiplesOfDepositTerm: this.fixedDepositProductsTemplate.inMultiplesOfDepositTerm ?? '',
       inMultiplesOfDepositTermTypeId: this.fixedDepositProductsTemplate.inMultiplesOfDepositTermType?.id ?? '',
+      renewalGracePeriodDays: this.fixedDepositProductsTemplate.renewalGracePeriodDays ?? '',
       minDepositAmount: this.fixedDepositProductsTemplate.minDepositAmount,
       maxDepositAmount: this.fixedDepositProductsTemplate.maxDepositAmount,
       nominalAnnualInterestRate: this.fixedDepositProductsTemplate.nominalAnnualInterestRate ?? 0,
@@ -171,6 +175,13 @@ export class FixedDepositProductTermsStepComponent implements OnInit, OnChanges
       maxDepositTermTypeId: [''],
       inMultiplesOfDepositTerm: [''],
       inMultiplesOfDepositTermTypeId: [''],
+      // Days after maturity a depositor can still walk in and have their FD renewed backdated to the
+      // original maturity date, at the currently active rate -- blank/0 keeps today's instant,
+      // same-night auto-renewal (see FD Dashboard for the manual renewal this enables).
+      renewalGracePeriodDays: [
+        '',
+        Validators.min(0)
+      ],
       minDepositAmount: [
         '',
         Validators.min(0)