class ConfigureWatch

Configures the fields of interest and wake triggers for this client connection.

The driver filters the requested masks against hardware capabilities and returns the

effective configuration in `effective_options`.

- **Partially supported options**: If some requested fields are supported and others are not

(e.g., requesting passive fields like `voltage_uv` or `current_ua` that do not support

active interrupt notifications), the driver enables the supported fields and returns the

active subset in `effective_options`. The call succeeds (`Ok`).

- **Fully unsupported options**: If non-empty masks were specified but NONE of the requested

fields are supported, the driver returns `NOT_SUPPORTED`.

If `ConfigureWatch` is never called, `Watch` defaults to returning on ANY supported field

change. The driver aggregates constraints across all clients to determine hardware reporting

rates.

`ConfigureWatch` may be called at any time, including while a `Watch` is pending. The new

masks take effect immediately and apply to that pending call. Change detection continues to

compare against the status last delivered on this connection, so a field that changed

before the reconfiguration can still resolve the pending `Watch`.

Parameters:

+ `options`: Requested watch options. Both `interest` and `wake_on` are optional.

Returns:

+ `effective_options`: The subset of requested options supported and enabled by the driver.

Errors:

- `NOT_SUPPORTED`: Non-empty options were requested, but none of the requested interest/wake

fields are supported by the driver.

On error the connection's configuration is left unchanged; a failed call never partially

applies.