Add add_fastapi option to Python template

[jsstevenson]

Feature description

Many of our projects reuse (or could stand to reuse) some FastAPI boilerplate. This feature should auto-add a template for them.

Use case

As a dev, I'd like to be setting up API service projects in a consistent manner with a baseline set of features.

Acceptance Criteria

Template features for the following-ish:

• FastAPI and Pydantic dependencies
• Basic Pydantic schema module
• Basic API service module
• Service info endpoint (app version, data versions, spec versions where possible)

Proposed solution

No response

Alternatives considered

No response

Implementation details

No response

Potential Impact

No response

Additional context

No response

Contribution

None