typescript: Add direct TLS negotiation support to Sequelize sample

**Is your feature request related to a problem? Please describe.**
Sequelize uses node-postgres under the hood, which currently doesn't support PostgreSQL 17's direct TLS negotiation feature. This prevents our Sequelize-based samples from taking advantage of improved connection performance.

**Describe the solution you'd like**
Once the upstream driver supports the feature, modify the sample to add support for the `sslnegotiation` connection parameter through Sequelize's connection options.

**Describe alternatives you've considered**
- Using pg-native through Sequelize's `native: true` option, but this requires additional platform dependencies and may not be supported in all environments.

**Additional context**
This feature was originally requested in #150 and has been broken out given many drivers already support this functionality.

Status upstream depends on node-postgres support, which can be tracked in #171.

First check node-postgres support in the upstream work tracked by #171; the issue names no sample file or test. Once available, locate the Sequelize sample's connection options and verify that sslnegotiation can be passed through; done means the sample supports the parameter without requiring pg-native.

Written by the indexing model from the issue text.