wip: handle chunked encoding in /Discover POST body

[vergenzt]

Should resolve #115

[ananyatimalsina]

Has this been tested with any recent version of IOS/macOS? #109 and #119 mention that Apple seems to have changed the airdrop protocol and thus only versions up to macOS Ventura and iOS 15 are supported, as stated by this project's README. My own tests (conducted with IOS 18) result in having to change

chunk_size = int(self.rfile.readline().rstrip(b"\r\n"),)
to
chunk_size = int(self.rfile.readline().rstrip(b"\r\n"), 16)

and finally conclude with a "No route to host" error on this line: self.rfile.read(), though I will have to investigate further whether this is caused by owl (However it does seem to be fine as it is showing peer add and remove logs) or perhaps even nexmon's monitor mode patch.