Specifically want to make it clear how this module is going to be
implemented, and lay down guidelines to be followed going forward.

Signed-off-by: JP-Ellis <josh@jpellis.me>

Signed-off-by: JP-Ellis <josh@jpellis.me>

This helps makes enums more manageable during logging and debugging.

The `D200` Ruff lint is ignored, ensuring that single-line docstrings
use the same formatting as the remaining docstrings.

Signed-off-by: JP-Ellis <josh@jpellis.me>

The `--broker-url` PyTest CLI argument is used by the examples to
determine whether a Broker is automatically launched, or whether an
existing broker is used.

All PyTest CLI arguments _must_ be defined in the root directory of the
project. As a result, the previous location where these arguments were
defined meant that the examples could only be launched of PyTest was
specifically pointed at the `examples/` directory.

This commit moves the definition to the root directory, thereby unifying
the `examples/` with the remaining tests.

Signed-off-by: JP-Ellis <josh@jpellis.me>

This (rather large) commit implements core functionality for the `Pact`
class, and the `Interaction` class to handle specific interactions
within a Pact.

This does _not_ implement every method that Pacts and/or interactions
might have (e.g., it is currently not possible to specify a Pact
version). The intent of this commit is to be a minimal working example
which can be improved upon more incrementally.

Signed-off-by: JP-Ellis <josh@jpellis.me>