- Add /confirm endpoint (section 4) — receives the loan data, formats
display strings, persists context to Redis keyed by reference_number
- /send-otp now requires reference_number; resend reuses the same
endpoint (no separate /resend-otp)
- /submit-otp requires reference_number and returns a new one for /submit
- /submit now takes only pin + reference_number; loan data is loaded
from Redis
- Rename term label '3 Bulan' to '3x Cicilan' across all examples