Ship the iOS beta through TestFlight instead of sideload-only?

[sepehr856-sudo]

The iOS build is currently an unsigned IPA that has to be sideloaded. That
works, but it locks out the people the app is otherwise perfect for: iPhone
and iPad users with no computer, since on iOS 26 a sideload without a machine
needs a signing certificate most users don't have.

TestFlight would remove that wall:

• a public link, two taps, no AltStore, Sideloadly or cable
• up to 10,000 external testers
• 90 days per build, then a re-upload (the CI already produces the IPA)
• external testing needs one App Review pass; internal testers skip it

The blocker is the $99/yr Apple Developer Program membership, which the repo
suggests isn't there yet (CODE_SIGNING.md still reads "once Concat has a
signing certificate"). AltStore PAL isn't a substitute — it's EU, Japan and
Brazil only.

So: would you consider it if the fee were covered? I'm willing to sponsor the
first year. If TestFlight is a no for now, an ad-hoc build with testers' UDIDs
registered would also work, but that needs the same account, so it's the same
decision.