initialize_session cannot pass params the SDK does not model

[mrwogu]

Problem

AsyncDroidClient.initialize_session builds its JSON-RPC params from a closed allowlist (client.py:253-350 in 0.1.2): every field is set through _set_if_not_none, and there is no way to add one the SDK does not model. The protocol object that owns send_request is reachable only through the private _ensure_protocol(), and neither it nor the protocol class is exported in droid_sdk.__all__.

Consequence: any field droid.initialize_session accepts on the wire is unreachable from the SDK until a new SDK release models it. A caller pinned to a published version has no supported workaround, only private-attribute access.

The same limitation applies to load_session, which models four fields, and to every other wrapped method whose parameter set is narrower than the protocol's.

Impact

• Protocol features ship without being usable from Python until an SDK release catches up (Python SDK 0.1.2 is behind the current Droid JSON-RPC surface #3 tracks how wide that gap currently is).
• Callers that need one unmodeled field must either wait or reach into client._ensure_protocol(), which is private and can break in any patch release.
• Reproducing a Droid CLI behaviour from Python is not always possible, so bug isolation against the JSON-RPC layer has to leave the SDK.

Ask

1. Escape hatch on the wrapped session methods, for example extra_params: dict[str, Any] | None = None, merged into params after the modeled fields. Either raise on collision with a modeled field or let the explicit argument win, as long as the rule is documented.
2. Alternatively, or in addition, a supported low-level entry point such as AsyncDroidClient.send_request(method, params, timeout), so callers can reach protocol surface the SDK does not yet wrap.
3. Whichever path you pick, document it as the intended pattern for protocol features that are newer than the installed SDK.

Environment

• droid-sdk 0.1.2 (PyPI)
• droid CLI 0.198.0
• Python 3.11, macOS 25.5.0