Add DMG background images and update asset management

- Introduced new background images for macOS DMG packaging, including standard and retina versions.
- Updated the finalize-desktop-artifacts.mjs script to check for the presence of these background images, enhancing error handling.
- Refactored the ensureMacDmgAssets function to improve asset validation and streamline the DMG building process.

scripts/finalize-desktop-artifacts.mjs

@@ -190,13 +190,19 @@ function cleanStagingArtifacts(keepNames) {
 }
 
 const MAC_DMG_ASSETS_DIR = path.join(rootDir, "packaging/macos/dmg");
+const MAC_DMG_BACKGROUND_PATH = path.join(rootDir, "assets/dmg/background.png");
+const MAC_DMG_BACKGROUND_RETINA_PATH = path.join(
+  rootDir,
+  "assets/dmg/background@2x.png",
+);
 const MAC_DMG_APP_NAME = "Farm Control Server.app";
+const MAC_DMG_WINDOW_WIDTH = 380;
+const MAC_DMG_WINDOW_HEIGHT = 540;
 
-async function ensureMacDmgAssets() {
+function ensureMacDmgAssets() {
   mkdirSync(MAC_DMG_ASSETS_DIR, { recursive: true });
 
   const voliconPath = path.join(MAC_DMG_ASSETS_DIR, "volicon.icns");
-  const backgroundPath = path.join(MAC_DMG_ASSETS_DIR, "background.png");
   const iconsetPath = path.join(rootDir, "assets/icon.iconset");
 
   if (!existsSync(voliconPath) && existsSync(iconsetPath)) {
@@ -213,16 +219,19 @@ async function ensureMacDmgAssets() {
     }
   }
 
-  if (!existsSync(backgroundPath)) {
-    const { Jimp } = await import("jimp");
-    const background = new Jimp({ width: 700, height: 450, color: "#1f1f1f" });
-    await background.write(backgroundPath);
-    console.log(`finalize-desktop-artifacts: generated DMG background at ${backgroundPath}`);
+  if (!existsSync(MAC_DMG_BACKGROUND_PATH)) {
+    throw new Error(`DMG background not found at ${MAC_DMG_BACKGROUND_PATH}`);
+  }
+
+  if (!existsSync(MAC_DMG_BACKGROUND_RETINA_PATH)) {
+    console.warn(
+      `finalize-desktop-artifacts: retina DMG background not found at ${MAC_DMG_BACKGROUND_RETINA_PATH}`,
+    );
   }
 
   return {
     volicon: existsSync(voliconPath) ? voliconPath : null,
-    background: existsSync(backgroundPath) ? backgroundPath : null,
+    background: MAC_DMG_BACKGROUND_PATH,
   };
 }
 
@@ -260,19 +269,19 @@ function buildMacDmgWithCreateDmg(
     "200",
     "120",
     "--window-size",
-    "700",
-    "450",
+    String(MAC_DMG_WINDOW_WIDTH),
+    String(MAC_DMG_WINDOW_HEIGHT),
     "--icon-size",
     "120",
     "--icon",
     appBundleName,
-    "180",
-    "200",
+    "98",
+    "270",
     "--hide-extension",
     appBundleName,
     "--app-drop-link",
-    "520",
-    "200",
+    "282",
+    "270",
     "--format",
     "UDZO",
   ];
@@ -367,7 +376,7 @@ async function buildMacDmg(appBundlePath, arch) {
   }
 
   let builtDmgPath;
-  const dmgAssets = await ensureMacDmgAssets();
+  const dmgAssets = ensureMacDmgAssets();
 
   try {
     builtDmgPath = buildMacDmgWithCreateDmg(