ci: latest CI update before 3.0.0 release

[michalChrobot]

Purpose of this PR

This PR does the following updates before 3.0.0 relese:

1. I update our CI configuration + Wrench
2. I update the minimal supported editor
3. I'm not adding any hard dependency on already released N4Ev6.7.0 as the latest editor (which we are using as minimal supported one) still has it as core-package which will cause a mismatch. We need to wait for 7.0.0 to actually release
4. I also updated testproject and minimal project to such editor
5. At the end I won't try to add coreclr here but rather I will create a separate ticket for it

Jira ticket

N/A

Documentation

N/A

Testing & QA (How your changes can be verified during release Playtest)

Main goal here is to see if Full CI will still be green (expectation)

Up-port

N/A

Backports

N/A

[u-pr]

💡 Harness Review

The CI and release-metadata updates are broadly consistent, but the unified-test template now refers to a platform collection that the project metadata does not define.

_{Reviewed commit e24ed74}

_{🤖 Helpful? 👍/👎}

[michalChrobot]

This was removed as it's covered by minimal editor now

[michalChrobot]

Removed as it's the same as default test platform

[michalChrobot]

/review

[u-pr]

💡 Harness Review

The Unified CI matrix now consistently targets the default validation editor and platform, but its manifest swap leaves that job running against stale test-project package versions.

_{Reviewed commit 7c9716c}

_{🤖 Helpful? 👍/👎}

[codecov-github-com]

Codecov Report

All modified and coverable lines are covered by tests ✅

@@              Coverage Diff               @@
##           develop-3.x.x    #4151   +/-   ##
==============================================
  Coverage          78.18%   78.18%           
==============================================
  Files                153      153           
  Lines              26272    26272           
==============================================
  Hits               20542    20542           
  Misses              5730     5730           

Flag	Coverage Δ
NGOv2_project_testproject_ubuntu_pinnedTrunk	77.82% <ø> (?)

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Components	Coverage Δ
com.unity.netcode.gameobjects	78.18% <ø> (ø)

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