feat: add step.raw_response pipeline step for non-JSON HTTP responses

[Copilot]

• Create module/pipeline_step_raw_response.go — RawResponseStep implementation
• Create module/pipeline_step_raw_response_test.go — 9 test cases
• Register step.raw_response in plugins/pipelinesteps/plugin.go
• Fix mis-indentation of step.raw_response in manifest StepTypes slice
• Update package comment to include raw_response
• Update plugin_test.go expectedSteps list and hardcoded counts from 28→29
• All tests pass, 0 lint issues

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[Copilot]

Pull request overview

Adds a new pipeline step type (step.raw_response) to allow HTTP-triggered pipelines to return non-JSON responses (e.g., XML/HTML/plain text) while stopping further pipeline execution and marking the response as handled.

Changes:

• Implemented RawResponseStep with configurable content_type, status, headers, and raw body/body_from (with template resolution for body).
• Added unit tests covering common response types, headers/status customization, template resolution, body_from, no-writer fallback, and config validation.
• Registered the new step type in the pipeline-steps plugin manifest and factory map.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
plugins/pipelinesteps/plugin.go	Registers step.raw_response in the plugin manifest StepTypes and StepFactories map
module/pipeline_step_raw_response.go	Implements the new RawResponseStep for writing non-JSON HTTP responses
module/pipeline_step_raw_response_test.go	Adds test coverage for raw response behaviors and validation

[intel352]

@copilot apply changes based on the comments in this thread

Also fix the failing tests.

[Copilot]

@copilot apply changes based on the comments in this thread

Also fix the failing tests.

Applied all review comments in 92ee45d:

• Fixed step.raw_response indentation in the manifest StepTypes slice
• Updated package-level comment to include raw_response
• Fixed failing tests: added step.raw_response to expectedSteps in TestStepFactories and updated the hardcoded count in TestPluginLoads from 28 → 29