Restore explanatory comments

Author: guitaripod

Sources/PackLib/Packer.swift

@@ -147,8 +147,13 @@ public struct Packer: Sendable {
                     let resolvedName = frameworkName ?? findFrameworkName(for: name, in: binDir) ?? name
                     let src = URL(fileURLWithPath: "\(resolvedName).framework/\(resolvedName)", relativeTo: binDir)
                     guard FileManager.default.fileExists(atPath: src.path) else {
+                        // if we can't find the binary, it might be a static framework that SwiftPM
+                        // did not copy into the .build directory. we don't need to pack it anyway.
                         break
                     }
+                    // if the binary is a static archive, don't embed it.
+                    // https://github.com/apple/llvm-project/blob/e716ff14c46490d2da6b240806c04e2beef01f40/llvm/include/llvm/Object/Archive.h#L33
+                    // swiftlint:disable:previous line_length
                     if !isStaticBinary(at: src) {
                         try await packFile(
                             srcName: "\(resolvedName).framework",