LangStream has no Windows support

[devinbost]

I discovered that our installation instructions don't work for Windows.
We need to make sure that Windows users can get LangStream running.

[vertigobo]

I am using langstream-cli-0.6.0 on Windows.
I get a java.lang.UnsupportedOperationException on ai.langstream.cli.commands.docker.LocalRunApplicationCmd.makeDirOrFileReadable() because it uses Files.setPosixFilePermissions(...).
I suggest to replace the POSIX file permissions with setReadable() setWritable() and setExecutable() of the File class.