fix: address PR review comments

- Set PathToAdd = TargetParent in the file-extension branch so AddToPath
  prepends the directory, not the file itself
- Return early after Write-Error when the parent directory is missing so
  AddToPath and subsequent steps are not reached with Path unset
- Guard New-Item directory creation behind Install action so Test runs
  do not mutate the filesystem
- Fix CHANGELOG wording to include 'windows' in the platform list

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: HeyItsGilbert

CHANGELOG.md

@@ -9,7 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
-- `FileDownload` is now supported on all platforms (`core`, `macos`, `linux`); there was no Windows-only code blocking this (#98).
+- `FileDownload` is now supported on all platforms (`windows`, `core`, `macos`, `linux`); there was no Windows-only code blocking this (#98).
 - `FileDownload` relative `Target` paths are now rooted against `$PWD` before resolution, matching the intuitive expectation of callers (#49).
 
 ### Fixed

PSDepend/PSDependScripts/FileDownload.ps1

@@ -94,22 +94,22 @@ if (Test-Path $Target -PathType Leaf) {
 }
 elseif ([IO.Path]::GetExtension($Target) -and -not (Test-Path $Target -PathType Container)) {
     # Target has a file extension — treat as a full destination file path
+    $PathToAdd = $TargetParent
     if (-not (Test-Path $TargetParent)) {
         Write-Error "Could not find parent path [$TargetParent] for target [$Target]"
         if ($PSDependAction -contains 'Test') {
             return $False
         }
+        return
     }
-    else {
-        $Path = $Target
-        $ToInstall = $True
-        Write-Verbose "Target has extension, treating as file path [$Target]"
-    }
+    $Path = $Target
+    $ToInstall = $True
+    Write-Verbose "Target has extension, treating as file path [$Target]"
 }
 else {
     # No extension (or already a container) — treat target as a directory
     Write-Verbose "[$Target] is a container, creating path to file"
-    if (-not (Test-Path $Target)) {
+    if (-not (Test-Path $Target) -and $PSDependAction -contains 'Install') {
         New-Item -ItemType Directory -Path $Target -Force | Out-Null
     }
     If ($Name) {