angryip/ipscan — reverse-engineered prompt

Build me a fast, friendly desktop network scanner like Angry IP Scanner. I want to be able to enter an IP range, or just scan my local network, and quickly see which addresses respond in a simple native looking window. It should feel lightweight, work on Linux, Windows, and macOS, and be packaged so I can build it for my current machine and launch it easily.

Please use the existing Java codebase and get it into a state where it builds cleanly, opens the GUI, and produces runnable app files in the usual build output. If there are already platform specific packaging options, make sure those work too where practical. Focus on making the core scan flow solid and the app pleasant to use, not on adding random extra features. If something is unclear, check the current docs online and make the sensible choice.