Message pagination now constrains client-provided cursors to the
PostgreSQL integer range used by `messages.id`, preventing oversized
values from raising database errors while preserving before/after
pagination semantics.
## Closes
-
[CW-7922](https://linear.app/chatwoot/issue/CW-7922/harden-backend-paths-causing-production-sentry-errors)
- [Sentry 7663397140](https://chatwoot-p3.sentry.io/issues/7663397140/)
- [Sentry 7663397546](https://chatwoot-p3.sentry.io/issues/7663397546/)
- [Sentry 7663464772](https://chatwoot-p3.sentry.io/issues/7663464772/)
## How to reproduce
Request conversation messages with an extremely large `before` or
`after` cursor, such as `4611686018427387903`. PostgreSQL previously
rejected the value as outside the range for the integer `messages.id`
column.
## What changed
- Normalize message cursors before they reach the query.
- Clamp them to the valid signed 32-bit integer ID range.
- Cover oversized `before` and `after` cursors with finder specs.
b3a1dbca81