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/environments/.env.ts

@@ -9,8 +9,8 @@
 /* tslint:disable */
 export default {
   'mifos_x': {
-    'version': '260520',
-    'hash': 'bf3e26a0'
+    'version': '260521',
+    'hash': '846b2484'
   },
   'allow_switching_backend_instance': true
 };