serde support for `TextUuid`

[zyllian]

Motivation

Without TextUuid implementing Serialize and Deserialize, models cannot implement them without using custom serializers/deserializers for each field that uses a TextUuid.

Proposed Solutions

1. Add a new feature which enables the uuid crate's serde feature, or
2. Always pull in uuid with serde enabled

Then defer serialization/deserialization to the uuid crate's implementations.