Fix types to allow fractional order quantities

[AshishMBakshi]

The order API supports fractional quantities for markets whose minimumTradeQty is below one, and order responses can contain fractional quantity, cumQuantity, and leavesQuantity values. The current TypedDicts declare all five order quantity fields as int, so static type checkers reject valid create/modify requests and incorrectly describe fractional responses.

This changes those annotations to int | float. Keeping int in the union preserves the natural whole-contract call shape while accurately accepting the decimal JSON numbers supported by the API.

Example currently rejected by mypy/pyright:

from polymarket_us.types.orders import CreateOrderParams

params: CreateOrderParams = {
    "marketSlug": "example-market",
    "intent": "ORDER_INTENT_BUY_LONG",
    "quantity": 0.84,
}

Affected fields:

• Order.quantity
• Order.cumQuantity
• Order.leavesQuantity
• CreateOrderParams.quantity
• ModifyOrderParams.quantity

If maintainers prefer a single numeric alias, the same change could use a Quantity = int | float alias. Decimal is not appropriate for response typing unless the SDK JSON decoder is also configured to return Decimal.

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Note

Low Risk
Type-only annotation changes with no runtime behavior; low risk aside from slightly broader static typing for quantity fields.

Overview
Updates order-related TypedDict annotations so quantity fields match the API’s support for fractional sizes (e.g. when a market’s minimum trade size is below one).

quantity, cumQuantity, and leavesQuantity on Order, plus quantity on CreateOrderParams and ModifyOrderParams, are now typed as int | float instead of int. Whole-number quantities remain valid; static checkers no longer reject decimal literals in create/modify payloads or mis-type fractional values in responses.

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