Allow including tag-message in changelog

[chrichrichri]

Is there an existing issue or pull request for this?

• I have searched the existing issues and pull requests

Feature description

To have a "headline" for a release, it would be great allow including tag-messages (of release tags) into the changelog. For example, a changelog including this headline could look like this:

# Changelog

All notable changes to this project will be documented in this file.

## [1.0.1] - 2021-07-18

This is the release-tag message

### Miscellaneous Tasks
- Add release script

### Refactor

- Expose string functions

Desired solution

Provide variable (such as tag_message) to the context, so it can be used as a variable within the changelog template.

Alternatives considered

N/A

Additional context

No response

[welcome]

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[orhun]

Pretty good idea! The implementation should be pretty straightforward thanks to Tag::message method. Marked as good first issue.

[alerque]

This will get into cart vs. horse territory for many projects as the finished changelog is expected inside the tagged commit not later. Perhaps an env var could be used to hold the tag message and then used both for the changelog and subsequent actual tag message.

[orhun]

Or maybe we can add a new argument similar to --with-commit such as --tag-message?