Add cancellation token support in precompiled query context generation

[SerhiiKozachenko]

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        Fixes #bugnumber

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[roji]

Thanks. LGTM.

[Copilot]

Pull request overview

Adds cancellation token propagation to the generated interceptor code for precompiled queries by assigning the incoming CancellationToken argument onto the runtime QueryContext prior to execution.

Changes:

• Detect CancellationToken parameters during captured-variable processing in precompiled query interceptor generation.
• Emit code to set precompiledQueryContext.QueryContext.CancellationToken from the operator argument.