Discover plugins automatically

[illright]

This PR marks an important internal architectural milestone — decoupling the steiger package from the @feature-sliced/steiger-plugin dependency while still retaining zero-config operation.

[changeset-bot]

🦋 Changeset detected

Latest commit: f61536f

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@steiger/toolkit	Minor

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[Copilot]

Pull Request Overview

This PR decouples the steiger package from the @feature-sliced/steiger-plugin dependency while retaining zero-config operation, and improves testing support by updating import paths to use the new @steiger/toolkit/test entrypoint. It also introduces new integration tests and utility functions to further validate plugin discovery and overall functionality.

• Updated import paths in test files across the steiger-plugin-fsd package.
• Added integration test utilities (e.g., get-snapshot-path, get-repo-root-path) and tests for plugin discovery.
• Updated snapshots and package dependencies in pretty-reporter and examples to reflect the decoupled architecture.

Reviewed Changes

Copilot reviewed 71 out of 71 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
packages/steiger-plugin-fsd/*	Updated test imports to refer to the new test entrypoint from @steiger/toolkit/test.
packages/pretty-reporter/package.json	Added vitest dependency to support updated testing.
integration-tests/utils/*	New utility functions to support integration tests.
integration-tests/tests/*	New integration tests for auto plugin discovery and updated snapshot validations.
.changeset/curly-years-sparkle.md	Changeset documenting the vitest-related refactoring.

Comments suppressed due to low confidence (1)

integration-tests/tests/discover-plugins.test.ts:138

• [nitpick] Consider renaming the parameter 'process' to 'childProcess' to avoid potential confusion with the Node.js global process object.

function getNewProcessOutput(process: ChildProcess, { until, stream = 'stdout' }: { until?: string; stream?: 'stdout' | 'stderr' } = {}): Promise<string> {