Scripts work under pwsh on Linux and macOS

Home, VS Code user folder and CLI are resolved per platform (with
VSCODE_USER_DIR as an override); dev-link makes a symlink where a
junction is not available.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0169iPWwKHZoBTNN9qwXiwqk

scripts/dev-link.ps1

@@ -38,7 +38,7 @@ $ErrorActionPreference = 'Stop'
 . (Join-Path $PSScriptRoot 'common.ps1')
 
 $config = Get-SetupConfig
-$extensionsDir = Join-Path $env:USERPROFILE '.vscode\extensions'
+$extensionsDir = Join-Path (Get-HomeDir) '.vscode/extensions'
 if (-not (Test-Path $extensionsDir)) {
     New-Item -ItemType Directory -Path $extensionsDir -Force | Out-Null
 }
@@ -103,7 +103,9 @@ foreach ($extension in $extensions) {
                "(it may be a real installed copy).")
     }
 
-    New-Item -ItemType Junction -Path $link -Target $source | Out-Null
+    # A junction needs no privilege on Windows; elsewhere a plain symlink does the same job.
+    $linkType = if (Test-IsWindows) { 'Junction' } else { 'SymbolicLink' }
+    New-Item -ItemType $linkType -Path $link -Target $source | Out-Null
     Write-Host "linked $linkName -> $source" -ForegroundColor Green
 }