update links in Markdown documentation

[danthe1st]

This PR fixes various dead links/outdated references in the README.md, RELEASE.md and RELENG.md files.

I also made some minor text changes where the old text seems to be no longer applicable (e.g. about the automated acknowledgement generation). However, please note that I don't know how the releng tooling works so I might have made wrong assumptions somewhere (and there may be things I've missed).

For example, there are the following things I'm not sure about:

• The RELEASE.md mentions the following for N&Ns:

  Create a tracking issue in the eclipse.platform.releng.aggregator repo (see N&N for 4.36 as an example).

  Is this still done? I only see one for tips and tricks.

• I saw a mention of helpdesk issues for creating splashscreens like that one. From what I can see, the one for 2026 doesn't seem to be present even though 2025-09 has been released already. Was there a process change or did someone forget about the issue (we are getting a new splashscreen in 2026, right (sorry but I had to)?

• I also noticed that RELENG.md mentions JobDSL and a differentiation between job for normal jobs and pipelineJob for jobs that should be run on Kubernetes but the actual .jenkinsfiles seem to be using agent {} blocks for this. Is this still up-to-date (I don't know JobDSL or the changes that have been made there).

• For RELENG.md, I changed the link format to []() syntax with relative paths for folders as that works on GitHub (and should also be fine/not show errors due to it being an invalid link when viewing the file in Eclipse).

[HannesWell]

Thank you for providing this. Many changes look good.
I have to admit that I haven't fully updated the documentation yet to consolidate it with all the RelEng automation that was implemented in the (more or less) recent past.
But I plan to do it in the next days (but probably I wont have time for it before preparing the new release cycle on Friday) and will then review this in detail along with that other change.
I'm writing this here as it will just remove some parts that are fixed here and I then don't have to go through the doc twice.

• I saw a mention of helpdesk issues for creating splashscreens like that one. From what I can see, the one for 2026 doesn't seem to be present even though 2025-09 has been released already. Was there a process change or did someone forget about the issue (we are getting a new splashscreen in 2026, right (sorry but I had to)?

That's a good catch and I'm not aware of any work going on in this regard, but from the timeline we should start it soon.
@MohananRahul do you know if anything is going on or who takes care of this or will you take care of this?

• I also noticed that RELENG.md mentions JobDSL and a differentiation between job for normal jobs and pipelineJob for jobs that should be run on Kubernetes but the actual .jenkinsfiles seem to be using agent {} blocks for this. Is this still up-to-date (I don't know JobDSL or the changes that have been made there).

Yes that section is obsolete since I have migrated all jobs to be defined as declarative Jenkins pipeline and to have their own .jenkinsfile. In general my recommendation is to always define as declarative pipeline directly in a Jenkins-File (and nobody objected when I implemented that).
But I wan to clean that up during the doc-cleanup I mentioned above.

[MohananRahul]

• I saw a mention of helpdesk issues for creating splashscreens like that one. From what I can see, the one for 2026 doesn't seem to be present even though 2025-09 has been released already. Was there a process change or did someone forget about the issue (we are getting a new splashscreen in 2026, right (sorry but I had to)?

That's a good catch and I'm not aware of any work going on in this regard, but from the timeline we should start it soon. @MohananRahul do you know if anything is going on or who takes care of this or will you take care of this?

Although I normally create this issue during the Q4 RC2 promotion, Issue created https://gitlab.eclipse.org/eclipsefdn/helpdesk/-/issues/6906