- Add NotificationChannelPort domain port for SMS/transactional channels.
- Refactor StringeeSmsService to implement the port; routes OTP template
keys through the tighter otp bucket and transactional keys through the
wider bucket.
- Add SmsRateLimiterService using a Redis sorted-set sliding window with
per-minute + per-hour limits per phone; fails open on Redis errors.
- Rate-limit violations throw DomainException(TOO_MANY_REQUESTS, 429)
with retryAfterSeconds in the details payload.
- Cover adapter + rate limiter with unit tests (22 specs); all 148
notifications tests still green.
Co-Authored-By: Paperclip <noreply@paperclip.ing>
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