Fix prefix false-positive in skip check, cap download throttle at 8, isolate test cache artifacts

- Installed-font skip now matches 'Ubuntu Nerd Font*' instead of
  'Ubuntu*' so Ubuntu no longer false-matches UbuntuMono (thread #37)
- Download throttle fixed at 8 instead of ProcessorCount to keep network
  usage bounded on high-core CI hosts (thread #36)
- Deduplication test uses a test-only cache tag and cleans up the full
  directory so no artifacts persist in user cache (thread #38)

Author: MariusStorhaug

src/functions/public/Install-NerdFont.ps1

@@ -135,7 +135,7 @@ Please run the command again with elevated rights (Run as Administrator) or prov
             if (-not $Force -and $installedFamilies) {
                 $alreadyInstalled = $false
                 foreach ($family in $installedFamilies) {
-                    if ($family -like "$fontName*") { $alreadyInstalled = $true; break }
+                    if ($family -like "$fontName Nerd Font*") { $alreadyInstalled = $true; break }
                 }
                 if ($alreadyInstalled) {
                     Write-Verbose "[$fontName] - already installed, skipping"
@@ -151,7 +151,7 @@ Please run the command again with elevated rights (Run as Administrator) or prov
         $httpClient.Timeout = [System.Threading.Timeout]::InfiniteTimeSpan
         $pending = [System.Collections.Generic.List[object]]::new()
         $readyToInstall = [System.Collections.Generic.List[object]]::new()
-        $throttle = [Math]::Max(1, [Environment]::ProcessorCount)
+        $throttle = 8
 
         try {
             foreach ($nerdFont in $toProcess) {

tests/NerdFonts.Tests.ps1

@@ -132,7 +132,7 @@ Describe 'Module' {
             } else {
                 Join-Path -Path $HOME -ChildPath '.cache/PSModule/NerdFonts'
             }
-            $cacheTagDir = Join-Path -Path $cacheRoot -ChildPath 'v3.4.0'
+            $cacheTagDir = Join-Path -Path $cacheRoot -ChildPath 'test-dedup-v0'
             $zipPath = Join-Path -Path $cacheTagDir -ChildPath 'DuplicateMonoTest.zip'
 
             try {
@@ -159,7 +159,7 @@ Describe 'Module' {
                 $script:NerdFonts = @(
                     [pscustomobject]@{
                         Name = $fontName
-                        URL  = 'https://github.com/ryanoasis/nerd-fonts/releases/download/v3.4.0/DuplicateMonoTest.zip'
+                        URL  = 'https://github.com/ryanoasis/nerd-fonts/releases/download/test-dedup-v0/DuplicateMonoTest.zip'
                     }
                 )
 
@@ -177,8 +177,8 @@ Describe 'Module' {
                 $script:InstalledFontFiles.Count | Should -Be 1
                 ($script:InstalledFontFiles | Select-Object -Unique).Count | Should -Be 1
             } finally {
-                if (Test-Path -LiteralPath $zipPath) {
-                    Remove-Item -LiteralPath $zipPath -Force -ErrorAction SilentlyContinue
+                if (Test-Path -LiteralPath $cacheTagDir) {
+                    Remove-Item -LiteralPath $cacheTagDir -Recurse -Force -ErrorAction SilentlyContinue
                 }
                 $script:NerdFonts = $originalFonts
                 Remove-Variable -Name InstalledFontFiles -Scope Script -ErrorAction SilentlyContinue