Fix issues with runaway tasks and broken iterators

[Tyrrrz]

General description

This PR improves reliability around command cancellation and event streaming.

It ensures that commands behave predictably when event consumers stop listening, avoids unobserved background failures, makes pull- and push-based event streams more consistent, and clarifies the dummy text generator’s output semantics.

Behaviors that changed

Scenario	Before	After
A consumer stops a pull event stream early	The command could block if it continued writing stdout or stderr.	Event delivery stops, while the command continues and its output is drained.
A command fails after a pull stream is disposed	Background failures could surface as unobserved task exceptions.	Detached failures are observed internally.
A stdin source faults after command cancellation	The late failure could become unobserved.	The late failure is observed internally.
A push-stream command completes immediately	Completion could be reported before the start event.	The start event is always reported before completion or failure.

[Copilot]

Pull request overview

This PR refactors internal async/event-stream plumbing and adds a small utility to prevent unobserved task exceptions from “detached” background work, particularly around event-stream cancellation scenarios.

Changes:

• Added TaskExtensions.ObserveException() to explicitly observe faults from tasks that may be abandoned after cancellation.
• Refactored pull/push event stream implementations to reduce detached-task/unobserved-exception risk and simplify flow.
• Renamed Channel<T> members for clearer semantics and updated affected call sites; adjusted related docs/comments and added a non-parallel test collection for global-state observation.

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
Readme.md	Minor punctuation tweak in documentation (i.e.,).
CliWrap/Utils/Extensions/TaskExtensions.cs	New helper to observe task exceptions via a fault-only continuation.
CliWrap/Utils/Channel.cs	Renames channel API/fields (Publish→Transmit, ReportCompletion→Close) for clearer intent.
CliWrap/EventStream/PushEventStreamCommandExtensions.cs	Refactors push-based event stream completion/error signaling and observes detached faults.
CliWrap/EventStream/PullEventStreamCommandExtensions.cs	Refactors pull-based event stream to close channel reliably and await command completion to avoid unobserved exceptions.
CliWrap/CommandResult.cs	Minor punctuation tweak in XML docs (i.e.,).
CliWrap/Command.Execution.cs	Improves stdin piping cancellation path to avoid unobserved exceptions after early cancellation.
CliWrap/Buffered/BufferedCommandExtensions.cs	Small refactor/cleanup of buffered execution pipeline wiring.
CliWrap.Tests/TestCollections.cs	Adds a non-parallel xUnit collection for tests observing global state.
CliWrap.Tests/CancellationSpecs.cs	Updates the race-condition regression test for unobserved task exceptions and disables parallelism for the suite.

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[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated 2 comments.

[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated no new comments.