Revert "[release/8.0] Bump STJ and MSBuild Version"

[steveisok]

Reverts #119859

VS17.10 can't support 8.0.5 and as a result this change needs to be backed out.

[Copilot]

Pull Request Overview

This PR reverts version bumps for System.Text.Json and MSBuild that were previously merged, downgrading them from 8.0.5/17.8.29 back to earlier versions (8.0.0-rc.1/17.8.3) to maintain compatibility with Visual Studio 17.10, which cannot support version 8.0.5.

Key changes:

• Reverts System.Text.Json from 8.0.5 to 8.0.0-rc.1.23406.6
• Reverts MSBuild from 17.8.29 to 17.8.3
• Updates related runtime dependencies and SHA references to align with the reverted versions

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
global.json	Reverts Microsoft.NET.Sdk.IL version from 8.0.10-servicing to 8.0.0-rc.1
eng/Versions.props	Reverts multiple package versions including System.Text.Json (8.0.5→7.0.3 for toolset, 8.0.5→8.0.0-rc.1 for runtime), MSBuild (17.8.29→17.8.3), and various related packages to earlier versions
eng/Version.Details.xml	Updates dependency entries and SHA references to align with the reverted package versions

[Copilot]

Pull Request Overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

[ViktorHofer]

We can revert this revert when VS 17.10 goes out of support (in Jan 2026). We should still not go higher than STJ/8.0.0.5 as that's the highest available assembly inbox in VS 17.12.

[hoyosjs]

/backport to release/8.0

[github-actions]

Started backporting to release/8.0 (link to workflow run)

[github-actions]

@hoyosjs backporting to release/8.0 failed, the patch most likely resulted in conflicts. Please backport manually!

git am output

$ git am --3way --empty=keep --ignore-whitespace --keep-non-patch changes.patch

Applying: Revert "[release/8.0] Bump STJ and MSBuild Version (#119859)"
Using index info to reconstruct a base tree...
M	eng/Version.Details.xml
M	eng/Versions.props
M	global.json
Falling back to patching base and 3-way merge...
Auto-merging eng/Version.Details.xml
CONFLICT (content): Merge conflict in eng/Version.Details.xml
Auto-merging eng/Versions.props
CONFLICT (content): Merge conflict in eng/Versions.props
Auto-merging global.json
error: Failed to merge in the changes.
hint: Use 'git am --show-current-patch=diff' to see the failed patch
hint: When you have resolved this problem, run "git am --continue".
hint: If you prefer to skip this patch, run "git am --skip" instead.
hint: To restore the original branch and stop patching, run "git am --abort".
hint: Disable this message with "git config set advice.mergeConflict false"
Patch failed at 0001 Revert "[release/8.0] Bump STJ and MSBuild Version (#119859)"
Error: The process '/usr/bin/git' failed with exit code 128

Link to workflow output