feat: senior citizen rate fix, joint ownership cap, FD/RD UI improvements

- Senior citizen interest rate correctly sent in FD/RD create payload
  (isSeniorCitizen, seniorCitizenInterestRate, nominalAnnualInterestRate override)
- Joint account ownership capped at 100%: Add Holder/Partner button disabled
  when 100% reached; dialog enforces remaining share as max across all account types
- FD/RD interest rate chart step: rate calculator with tenure, senior citizen toggle,
  maturity preview
- FD/RD preview step improvements
- Base FD interest rate chart component added under fixed-deposit-products
- Base recurring deposit interest rate chart component removed (replaced)
- Savings account details step: joint holder improvements
- Products routing and module updated for base FD rate chart

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/app/deposits/recurring-deposits/create-recurring-deposits-account/create-recurring-deposits-account.component.html

@@ -75,6 +75,7 @@
           [recurringDepositsAccountTemplate]="recurringDepositsAccountTemplate"
           [recurringDepositsAccountProductTemplate]="recurringDepositsAccountProductTemplate"
           [submittedOnDate]="submittedOnDate"
+          [cbsBaseRates]="cbsBaseRates"
           (tenureSelected)="handleTenureSelected($event)"
         >
         </mifosx-recurring-deposits-account-interest-rate-chart-step>
@@ -105,6 +106,8 @@
           [rdMaturityAmount]="rdMaturityAmount"
           [rdInterestEarned]="rdInterestEarned"
           [rdDaysInYear]="rdDaysInYear"
+          [rdAppliedRate]="rdAppliedRate"
+          [rdIsSeniorCitizen]="rdIsSeniorCitizen"
           (submitEvent)="submit()"
         >
         </mifosx-recurring-deposits-account-preview-step>

src/app/deposits/recurring-deposits/create-recurring-deposits-account/create-recurring-deposits-account.component.ts

@@ -77,10 +77,14 @@ export class CreateRecurringDepositsAccountComponent {
   recurringDepositsAccountTemplate: any;
   /** Recurring Deposit Account Product Template */
   recurringDepositsAccountProductTemplate: any;
+  /** Active CBS base interest rate versions */
+  cbsBaseRates: any[] = [];
   /** Selected tenure value and frequency from calculator */
   selectedTenureValue: number | null = null;
   selectedTenureFrequencyId: number | null = null;
   selectedDepositAmount: number | null = null;
+  rdAppliedRate: number | null = null;
+  rdIsSeniorCitizen = false;
 
   constructor() {
     this.route.data.subscribe((data: { recurringDepositsAccountTemplate: any }) => {
@@ -94,6 +98,10 @@ export class CreateRecurringDepositsAccountComponent {
    */
   setTemplate($event: any) {
     this.recurringDepositsAccountProductTemplate = $event;
+    this.productsService.getFdBaseInterestRates().subscribe({
+      next: (rates: any[]) => (this.cbsBaseRates = rates || []),
+      error: () => (this.cbsBaseRates = [])
+    });
   }
 
   /** Captures tenure selection from calculator */
@@ -101,6 +109,8 @@ export class CreateRecurringDepositsAccountComponent {
     this.selectedTenureValue = $event.depositPeriod;
     this.selectedTenureFrequencyId = $event.depositPeriodFrequencyId;
     this.selectedDepositAmount = $event.depositAmount;
+    this.rdAppliedRate = $event.appliedRate ?? null;
+    this.rdIsSeniorCitizen = $event.isSeniorCitizen ?? false;
   }
 
   /** Get Recurring Deposit Account Details Form Data */
@@ -283,6 +293,13 @@ export class CreateRecurringDepositsAccountComponent {
       recurringDepositAccount.mandatoryRecommendedDepositAmount = this.selectedDepositAmount;
     }
 
+    // Senior citizen rate override
+    if (this.rdIsSeniorCitizen && this.rdAppliedRate != null && this.rdAppliedRate > 0) {
+      recurringDepositAccount.isSeniorCitizen = true;
+      recurringDepositAccount.seniorCitizenInterestRate = this.rdAppliedRate;
+      recurringDepositAccount.nominalAnnualInterestRate = this.rdAppliedRate;
+    }
+
     const nominees = this.recurringDepositsAccountCurrencyStep?.nominees ?? [];
     if (nominees.length > 0) {
       recurringDepositAccount.nominees = nominees.map((n: any) => ({