feat(items): extract tier-1 item icons from the art sheet

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

tools/extract-item-icons.ps1

@@ -0,0 +1,65 @@
+# tools/extract-item-icons.ps1
+# Crops the Tier-1 item icons out of art/Items.png into apps/web/public/images/items.
+# Re-runnable: overwrites its own output and touches nothing else.
+$ErrorActionPreference = 'Stop'
+Add-Type -AssemblyName System.Drawing
+
+$root = Split-Path -Parent $PSScriptRoot
+$sheet = Join-Path $root 'art\Items.png'
+$ratPortrait = Join-Path $root 'art\enemies\AschenratteIcon.png'
+$outDir = Join-Path $root 'apps\web\public\images\items'
+New-Item -ItemType Directory -Force -Path $outDir | Out-Null
+
+function Export-Icon {
+  param(
+    [System.Drawing.Image] $Source,
+    [int] $X, [int] $Y, [int] $Size,
+    [string] $Key
+  )
+  $bitmap = New-Object System.Drawing.Bitmap 256, 256
+  $graphics = [System.Drawing.Graphics]::FromImage($bitmap)
+  $graphics.InterpolationMode = [System.Drawing.Drawing2D.InterpolationMode]::HighQualityBicubic
+  $graphics.DrawImage(
+    $Source,
+    (New-Object System.Drawing.Rectangle 0, 0, 256, 256),
+    (New-Object System.Drawing.Rectangle $X, $Y, $Size, $Size),
+    [System.Drawing.GraphicsUnit]::Pixel)
+  $graphics.Dispose()
+  $bitmap.Save((Join-Path $outDir "$Key.png"), [System.Drawing.Imaging.ImageFormat]::Png)
+  $bitmap.Dispose()
+  Write-Host "wrote $Key.png"
+}
+
+$items = [System.Drawing.Image]::FromFile($sheet)
+try {
+  # Rows 1-2: cells are 350 wide with a caption strip at the bottom, so the
+  # artwork is the 300x300 square inset by 25px horizontally.
+  $columns = 8, 366, 724, 1082
+  $rowOne = 'worn-short-sword', 'bandit-blade', 'ash-blade', 'bandit-hood'
+  $rowTwo = 'reinforced-leather-jacket', 'raider-gloves', 'guardsman-legs', 'ash-boots'
+
+  for ($i = 0; $i -lt 4; $i++) {
+    Export-Icon -Source $items -X ($columns[$i] + 25) -Y 8   -Size 300 -Key $rowOne[$i]
+    Export-Icon -Source $items -X ($columns[$i] + 25) -Y 364 -Size 300 -Key $rowTwo[$i]
+  }
+
+  # Row 3 is centred and shorter: three cells, 262x262 artwork inset by 44px.
+  $rowThreeColumns = 191, 549, 907
+  $rowThree = 'borderwatch-sigil', 'burned-captain-pendant', 'small-healing-potion'
+  for ($i = 0; $i -lt 3; $i++) {
+    Export-Icon -Source $items -X ($rowThreeColumns[$i] + 44) -Y 720 -Size 262 -Key $rowThree[$i]
+  }
+}
+finally {
+  $items.Dispose()
+}
+
+# STAND-IN ART: no Aschenfell artwork exists yet, so the pelt icon is a scorched
+# hide patch cropped from the Aschenratte portrait. Replace when real art lands.
+$rat = [System.Drawing.Image]::FromFile($ratPortrait)
+try {
+  Export-Icon -Source $rat -X 760 -Y 300 -Size 320 -Key 'ash-pelt'
+}
+finally {
+  $rat.Dispose()
+}