Update add-in invocation for unified manifest

[Rick-Kirkham]

The manifest doesn't play any part in invoking an add-in from an actionable message. But the developer consults the manifest to get two pieces of information. This PR tells the developer how to do that if the add-in uses the unified manifest.

[learn-build-service-prod]

PoliCheck Scan Report

The following report lists PoliCheck issues in PR files. Before you merge the PR, you must fix all severity-1 and severity-2 issues. The AI Review Details column lists suggestions for either removing or replacing the terms. If you find a false positive result, mention it in a PR comment and include this text: #policheck-false-positive. This feedback helps reduce false positives in future scans.

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[learn-build-service-prod]

Learn Build status updates of commit c41f23d:

✅ Validation status: passed

File	Status	Preview URL	Details
docs/actionable-messages/invoke-add-in.md	✅Succeeded	View

For more details, please refer to the build report.

[learn-build-service-prod]

Learn Build status updates of commit 82cf5bd:

✅ Validation status: passed

File	Status	Preview URL	Details
docs/actionable-messages/invoke-add-in.md	✅Succeeded	View

For more details, please refer to the build report.

[learn-build-service-prod]

PoliCheck Scan Report

The following report lists PoliCheck issues in PR files. Before you merge the PR, you must fix all severity-1 and severity-2 issues. The AI Review Details column lists suggestions for either removing or replacing the terms. If you find a false positive result, mention it in a PR comment and include this text: #policheck-false-positive. This feedback helps reduce false positives in future scans.

✅ No issues found

More information about PoliCheck

Information: PoliCheck | Severity Guidance | Term
For any questions: Try searching the learn.microsoft.com contributor guides or post your question in the Learn support channel.