feat: expose prefer-cache to create_device_manager caller

[Lash-L]

No description provided.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

Files with missing lines	Coverage Δ
roborock/devices/device_manager.py	90.15% <100.00%> (ø)

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[Copilot]

Pull request overview

This PR exposes the prefer_cache parameter to callers of the create_device_manager function, allowing them to control whether cached device data should be preferred over fetching fresh data from the API.

• Added prefer_cache parameter to create_device_manager function signature with default value of True
• Updated function docstring to document the new parameter
• Parameter is passed through to the internal discover_devices call

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[allenporter]

Another way we can do this is just clear the home data cache before calling into the integration. WDYT?

[Lash-L]

Another way we can do this is just clear the home data cache before calling into the integration. WDYT?

We don't want the cache cleared though right? as if we fail the home data call, we want to still try to setup

[allenporter]

Yes, sounds good.

[Lash-L]

Yes, sounds good.

It definitely makes the cache less helpful though. As we can get into a unfortunate situation where on startup we do a bunch of home data calls when theoretically the part that is stopping it from setting up is not the home data. But for now, it probably makes sense as is so users don't have to do anything crazy to get their new devices added.