Disclose host-added attribution before Slack sends

[christj99]

Summary

Add a connector-attribution preflight to slack-messaging so an agent:

• tells the user when its current host adds sender attribution
• pauses for an explicit choice before a real or scheduled post
• offers final text for manual paste when attribution-free delivery matters
• does not interrupt compose-only, rewrite-only, or draft-only work

This avoids surprising someone who asked the agent to post “as me,” especially for mass mentions or customer-facing messages.

Preview

Documentation and behavioral contract tests only.

Testing

• make lint
• make test-unit (20 passed)
• make typecheck

The LLM eval suite was not run locally because it requires GEMINI_API_KEY and SLACK_MCP_TOKEN.

Notes

The attribution is added by the host rather than the reviewed message body, so the skill does not promise that an edit can remove it.

Requirements

• I've read and understood the Contributing Guidelines and have done my best effort to follow them.
• I've read and agree to the Code of Conduct.
• I've run make test and the tests pass.

[salesforce-cla]

Thanks for the contribution! Before we can merge this, we need @christj99 to sign the Salesforce Inc. Contributor License Agreement.

[changeset-bot]

🦋 Changeset detected

Latest commit: 4682fc4

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

This PR includes changesets to release 1 package

Name	Type
slack	Patch

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