feat: Split the notice doc comment into a short summary string and additional documentation.

[bdferris-v2]

This is a usability tweak on the notice documentation support that was implemented in #1324.

We enforce that notice doc comments have the following form:

/**
 * Short text describing the notice in a single line (required).
 *
 * Additional text further describing the notice on new lines (optional).
 */

We represented that internally as a single combined comment string, but there are uses where we'd like to split out the short summary string and the additional optional documentation so that they can be used and rendered separately, where appropriate. This PR implements that split.

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• Format the title like "feat: [new feature short description]". Title must follow the Conventional Commit Specification(https://www.conventionalcommits.org/en/v1.0.0/).
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[github-actions]

✅ Rule acceptance tests passed.
New Errors: 0 out of 1428 datasets (~0%) are invalid due to code change, which is less than the provided threshold of 1%.
Dropped Errors: 0 out of 1428 datasets (~0%) are invalid due to code change, which is less than the provided threshold of 1%.
New Warnings: 0 out of 1428 datasets (~0%) are invalid due to code change, which is less than the provided threshold of 1%.
Dropped Warnings: 0 out of 1428 datasets (~0%) are invalid due to code change, which is less than the provided threshold of 1%.
0 out of 1428 sources (~0 %) are corrupted.
Commit: ce39f3e
Download the full acceptance test report here (report will disappear after 90 days).
✅ Rule acceptance tests passed.