Limit number of inlined pages per pipeline, not operator

[wendigo]

Description

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## Section
* Fix some things. ({issue}`issuenumber`)

[Copilot]

Pull Request Overview

This PR refactors the inlining behavior so that the limit on inlined pages is enforced at the pipeline level rather than per operator. Key changes include:

• Introduction of a new PipelineSpoolingController that aggregates inlining metrics using shared atomic counters.
• Adjustments in the SpoolingController interface and OperatorSpoolingController to align with the new design.
• Updates to tests and operator factory code to accommodate the new pipeline-level inlining limits.

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
core/trino-main/src/main/java/io/trino/operator/PipelineSpoolingController.java	Adds a new controller for pipeline-level inlining with atomic counters and updated logic in nextMode and execute.
core/trino-main/src/main/java/io/trino/operator/SpoolingController.java	Updates the interface with unwrap and a new MetricSnapshot record and ActionMetrics class.
core/trino-main/src/main/java/io/trino/operator/OperatorSpoolingController.java	Removes inline handling in nextMode and adjusts mode switching to support the new design.
core/trino-main/src/main/java/io/trino/operator/OutputSpoolingOperatorFactory.java	Refactors controller instantiation to wrap the OperatorSpoolingController with the PipelineSpoolingController.
core/trino-main/src/main/java/io/trino/operator/PipelineContext.java	Introduces new atomic counters and getter methods for inlined page metrics.
core/trino-main/src/test/java/io/trino/operator/TestSpoolingController.java	Updates tests to use the new PipelineSpoolingController and verifies the new behavior.

Comments suppressed due to low confidence (1)

core/trino-main/src/test/java/io/trino/operator/TestSpoolingController.java:169

• [nitpick] Directly unwrapping to OperatorSpoolingController ties the test to an implementation detail; consider exposing a method in the SpoolingController interface to retrieve the spooled segment target to decouple tests from a specific implementation.

assertThat(controller.unwrap(OperatorSpoolingController.class).getCurrentSpooledSegmentTarget())