feat: add combo market catalog

[cesarenaldi]

Adds typed Combo market catalog support to the Python SDK via list_combo_markets on sync/async public and secure clients.\n\nVerification:\n- uv run ruff format src/polymarket tests/unit/test_builder_trades.py tests/unit/test_streams_subscribe_router.py\n- uv run ruff check src/polymarket tests/unit/test_builder_trades.py tests/unit/test_streams_subscribe_router.py\n- uv run pyright\n- uv run pytest tests/unit/test_builder_trades.py tests/unit/test_streams_subscribe_router.py\n- Live smoke: PublicClient().list_combo_markets(page_size=1).first_page()

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Note

Low Risk
Additive read-only public API and transport plumbing; existing keyset pagination keeps default after_cursor behavior.

Overview
Adds typed Combo market catalog support: clients can page through RFQ combo-eligible markets via list_combo_markets, with optional exclude of CTF condition IDs.

Wires a new rfq HTTP service (environment.rfq_url, dedicated transport on sync/async public and secure clients, lifecycle close). KeysetPaginatedSpec gains a configurable cursor_param (default after_cursor); combo markets use cursor for pagination. New ComboMarket models normalize the API’s parallel outcome/price arrays into yes/no outcomes.

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[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[cursor]

Missing LTE pagination sentinel

Medium Severity

_parse_combo_markets_page treats any non-empty next_cursor string as a real cursor. Elsewhere in this SDK, LTE= is the documented end-of-pagination sentinel and is normalized to no next page via next_cursor_or_none. If the RFQ combo-markets API uses that sentinel, callers will see has_more true and issue another request with cursor=LTE= instead of stopping.

 

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