Initial implementation of APKINDEX, fetching, reading, parsing, & merging

Package.swift

@@ -3,13 +3,24 @@ import PackageDescription
 
 let package = Package(
   name: "darwin-apk",
+  platforms: [
+    .macOS(.v13),
+  ],
   dependencies: [
     .package(url: "https://github.com/apple/swift-argument-parser", from: "1.5.0"),
+    .package(url: "https://github.com/tsolomko/SWCompression", from: "4.8.6"),
   ],
   targets: [
+    .target(
+      name: "darwin-apk",
+      dependencies: [
+        .product(name: "SWCompression", package: "SWCompression"),
+      ],
+      path: "Sources/apk"),
     .executableTarget(
       name: "dpk",
       dependencies: [
+        "darwin-apk",
         .product(name: "ArgumentParser", package: "swift-argument-parser"),
       ],
       path: "Sources/dpk-cli"