Docs: clarify BaseSensorOperator parameters in Sensors guide

[jaymasiwal]

What this PR does

The core Sensors documentation did not clearly document parameters inherited from
BaseSensorOperator (e.g. poke_interval, timeout, mode, soft_fail), and
there was no obvious link to where these parameters are defined after the Task SDK
refactor.

This PR adds a dedicated “BaseSensorOperator parameters” section to the
Sensors guide that:

• Explains that all sensors inherit from BaseSensorOperator
• Documents commonly used sensor parameters in one place
• Links to the authoritative Task SDK API reference
• Includes a short example showing typical usage

Why this is needed

Because BaseSensorOperator now lives in the Task SDK, provider API pages do not
always expose inherited parameters clearly. This makes it unnecessarily hard for
users to discover and understand how sensors behave.

This change improves discoverability without altering any runtime behavior.

Scope

• Documentation only
• No code or behavior changes

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[jaymasiwal]

All checks are green now. Happy to adjust wording or structure if reviewers have suggestions.