Question

As stated in the question, but including code signing and embedding provisioning profiles.

Answer 1

I recently posted a series of blogs on how to build/test/deploy both iOS and Android apps using Jenkins running on the CloudBees PaaS: the iOS blog is online at
Continuous Deployment for Mobile Apps with Jenkins: Xcode builds with MacOS slaves

That blog post actually talks about Appaloosa, but the Jenkins configuration for TestFlight is almost identical: you can see an actual example config online here:
stockfishchess-ios Jenkins configuration

A few things to note:

• You need to make sure that the build number is unique – the best way to do this is just to get the Jenkins build number from the environment (see the example config).
• You need to configure the build job to package an .ipa archive (the example config uses the fast archive plugin to do this)
• You should copy the API Token and Team Token from your TestFlight Console

Re: iOS Provisioning – look at the Apple Developer Program docs for details on how to set up an Ad Hoc Provisioning profile, which you will need to send to your testers. Get their UDIDs for the devices they want to use, create the profile using the iOS Provisioning Portal and use the Xcode Organizer to export the .mobileprovision profile. You will also need to go into TestFlight and invite the beta test users.

You can find my contact details on the blogs – feel free to contact me directly if you need further help.