publish: return api.ErrCanceled when user declines interactive prompts

[ishwar170695]

What I did

Previously, declining the bind mount or sensitive data warning prompt caused publish() to return nil, which is indistinguishable from success for callers and automation scripts (exit code 0).

Change publish() to return the existing api.ErrCanceled sentinel so callers can detect user-initiated cancellation via errors.Is(). Add unit tests covering both the preChecks decline path and the full publish() path.

Signed-off-by: Ishwar chand meena ishwarcm@iitbhilai.ac.in

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[Copilot]

Pull request overview

This PR changes compose publish to return a detectable error when the user declines interactive safety prompts, instead of returning nil (success), so automation/callers can distinguish an abort from a successful publish.

Changes:

• Introduce a new sentinel error (ErrPublishAborted) and return it when pre-check prompts are declined.
• Add unit tests intended to cover “decline” paths for preChecks and publish.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
pkg/compose/publish.go	Returns a sentinel error when publish is aborted via interactive decline.
pkg/compose/publish_test.go	Adds tests for decline behavior in pre-checks and publish.

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[Copilot]

Pull request overview

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

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[ishwar170695]

Updated PR description to reflect the use of the existing api.ErrCanceled instead of creating a new custom error.