chore: add a release roadmap

[acolombier]

As new Mixxx contributor, I'm still struggling greatly with keeping track of the release schedule, so I thought I'd put together a document to keep track of our current release as well as the plan for future releases.

I tried a few Mermaid template, and this one seems to give the best visual. I'd be keen to get input on the data I have provisioned for future release, just to make sure I am in sync with the roadmap. These data will help with the milestone management. Note that we could also me this document to the wiki but I thought having it in the repo may make it more accessible and easier to keep in sync in the future.

Also removing an accidentally commited file

Tip

You might want to open the document to get the Mermaid diagram rendering

[acolombier]

Ideally, I'd like to get the placeholder dates completed with prevision dates

[Swiftb0y]

We need to introduce the introduction of this new directory on zulip. Until now all dev-facing docs were handled exclusively on the wiki and this would start bifurcating that.

[acolombier]

I'm happy to put that in the wiki!
I just thought I would open a PR so we can discuss this and I can use it to remove that dangling changelog backup

[Swiftb0y]

whats the advantage of documenting this here when the same information is already visible in the appropriate github release or tag or milestone?

[acolombier]

Not sure there is any advantage to be honest, I just thought it would make the timeline slightly easier to read but arguable we could truncate anything before the current release if you think this is just noise.

[daschuer]

I like the idea to have this information more visible. Maybe also on our web page?

We have decided for this:
https://github.com/mixxxdj/mixxx/wiki/250_release_proposal#proposal-1-phase-model
But have failed to publish our decision appropriate.
Later we have also decided to set a release date every 6 month for orientation, while the "As long as it takes" has priority (quality over scheduled dates)

Make sure we keep the decision valid.

Is it possible to relate your diagram to the calendar date?
Something like this?
https://de.wikipedia.org/wiki/Ubuntu_(Betriebssystem)
This one is also interesting:
https://launchpad.net/mixxx

[acolombier]

Maybe also on our web page?

I was thinking exactly that but not sure how the team would receive that document in general at first and also how Mermaid is supported in our web framework.

while the "As long as it takes" has priority (quality over scheduled dates)

100% makes sense. This is what I tried to capture in the info box:

> [!IMPORTANT]
> The date provided for the future release are purely indicative. The Mixxx Core Team reserves the right to adjust them in order to help with team availability and delays in tasks.

Can you think of a batter way to emphasise this point?

Is it possible to relate your diagram to the calendar date?

If you mean that diagram, I don't think Mermaid as any template for it, but I'll confirm that.

This one is also interesting:
https://launchpad.net/mixxx

Ah that's a bummer. I started making a branching diagram and decided to abandon the idea as it felt too convoluted. I will restart the idea so we can choose which one we prefer

[acolombier]

I couldn't find a way to make it look like your first example, but I was able to make something similar to the second. I don't find it very good, mainly due to Mermaid limitation, so I would suggest we keep the first one instead.

[daschuer]

I don't have a strict preference here. Something is better than nothing. We can all the time improve it.

[acolombier]

Please note that the main part of the PR has now been moved as a website page. I have rebased the commits to remove the unwanted CHANGELOG.

[Swiftb0y]

LGTM. Thank you.

[daschuer]

LGTM