fix(installer): pin background jobs to a local cwd — no UNC noise on roaming-profile machines

[LukasWodka]

Summary

Fixes the red RemoteException / CMD.EXE ... UNC paths are not supported blocks that appear 2–6 times per install on machines whose home directory is a UNC share (roaming profiles — the hospital/enterprise norm). Root cause: PowerShell background jobs start their runspace in $HOME, so every cmd /c inside a job inherits a UNC cwd. Observed live on a customer install (2026-07-27).

Change

• New shared $script:JobInit scriptblock — if ($env:SystemRoot) { Set-Location $env:SystemRoot } — passed as -InitializationScript at all five Start-Job sites (wsl --update, wsl --set-default-version 2, wsl --list, NVIDIA toolkit install + verify).
• Pester: AST gate asserting everyStart-Job in the script carries -InitializationScript (so new jobs can't regress), plus a behavioral test that the init block moves the job cwd and is a no-op when SystemRoot is unset (Linux CI).
• manifest.sha256 regenerated.

Type

Bug fix

Test plan

• Full Pester suite locally on pwsh 7.5 (mirrors CI invocation): 155 passed, 0 failed, 8 skipped (3 new).
• scripts/gen-manifest.sh run; --check clean.
• On a Windows box with a UNC home, wsl --update/toolkit steps no longer emit CMD.EXE UNC warnings (jobs run from C:\Windows).

🤖 Generated with Claude Code

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Note

Low Risk
Installer-only UX fix for job initialization; no auth, cluster, or credential logic changes.

Overview
Fixes misleading red RemoteException noise during Windows installs when the user profile home is a UNC path (common with roaming profiles). PowerShell Start-Job runspaces inherit that cwd, so nested cmd /c calls emit CMD’s “UNC paths are not supported” message even when WSL steps succeed.

Introduces $script:JobInit (Set-Location $env:SystemRoot when set) and passes it as -InitializationScript on all five Start-Job sites (WSL update/default version, WSL list, NVIDIA toolkit install/verify).

Pester adds an AST gate so every Start-Job in install-k8s.ps1 must include -InitializationScript, plus a behavioral test for the init block. manifest.sha256 is updated for the installer script.

^{Reviewed by Cursor Bugbot for commit 6132abf. Bugbot is set up for automated code reviews on this repo. Configure here.}

[LukasWodka]

bugbot run

[cursor]

✅ Bugbot reviewed your changes and found no new issues!

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^{Reviewed by Cursor Bugbot for commit 6132abf. Configure here.}

[shujaatTracebloc]

Reviewed the code, not just the CI state.

Completeness: exactly 5 Start-Job sites in install-k8s.ps1, all 5 now pass -InitializationScript $JobInit. No other job primitive (Start-ThreadJob/-AsJob/Invoke-Command) exists, so nothing was missed — and the AST-gate test makes that guarantee permanent.

Correctness:-InitializationScript runs in the job runspace before the main block, so Set-Location $env:SystemRoot moves cwd off the UNC share before any cmd /c inherits it. SystemRoot is always local on Windows; the guard makes it a no-op off-Windows. $script:JobInit is correctly script-scoped so the unqualified $JobInit inside the functions resolves.

No output pollution (the real risk): Set-Location without -PassThru emits nothing, so the parsed sites stay clean — $distroRaw (wsl --list) receives only $raw, and the update path keys off job State, not output. The behavioral test's Receive-Job … | Should -Be "ran" proves the init block contributes no output.

Manifest regenerated; drift check green. All CI green (Pester on windows + ubuntu); Bugbot clean on 6132abf.

LGTM 🚀

[shujaatTracebloc]

Backing-ref link: this PR landed the fix for #409 (background jobs pinned to a local cwd — no UNC noise). Merged to develop as ab940e5; the issue was closed manually since auto-close only fires on the default branch.