Use UUIDs

[pedro-gutierrez]

Is your feature request related to a problem? Please describe.

At the moment, primary keys in the database are generated by Postgres as integers and auto incremented.
This has the following disadvantages:

• it is not possible to anticipate the id of a category, item or mod until it is actually created.
• ids in the database are integers, while ids in GraphQL are strings. This forces us to implement type casting in both ways.

Describe the solution you'd like

As a software developer
I want to manage data with deterministic uuids
So that we can have a more resilient, interoperable backend with support for offline operations

• To change the datatype for all primary keys from integer to the native UUID type offered by Postgres.
• To include those ids in all GraphQL in input types, and them client generated, as universally unique identifiers.

Cost of not doing
We would be missing the following advantages:

• less impedance mismatch between GraphQL and Postgres.
• easier data migration between systems
• resiliency and idempotency
• offline operations, where the database is not available

How we may solve this
From a technical point of view, this would involve:

• Migrate existing tests
• Update existing GraphQL input types
• Adapt Ecto Schemas
• Implement migrations on all tables

Since this is a potentially big feature, we could approach this by contexts:

• Profiles
• AidTaxonomy
• Aid/Manifest Lists
• Users, Groups, Roles
• Shipments

Additional context

• Link to the original GitLab issue and follow up discussion with @coderbyheart: https://gitlab.com/masksfordocs/toolbox/-/issues/109