feat: Extend Order API with commission_type

[matebudai]

Context

Extend Order API with a new field called commission_type.

Possible values:

• notional(default, API backward compatible so that when type is not specified notional is assumed)
• qty(charge commission on a per quantity basis, which make it possible to charge commission on per contract basis in case of options)
• bps

class CommissionType(str, Enum):
    """
    Represents the available ways of charging commission. This determines how
    the value in the commission field is interpreted.
    """

    NOTIONAL = "notional"
    BPS = "bps"
    QTY = "qty"

Changes

• Introduce the new enum type.
• Extend broker API order request model with the new field.
• poetry update black

[hiohiohio]

Overall LGTM! Left small comments.

[hiohiohio]

Nice!

[hiohiohio]

something like this?

Suggested change

	assert mo_response.commission == 1.25
	assert mo_response.commission == 0
	assert mo_response.commission_bps == 100

[matebudai]

Fixed.
efc9a61