scripts(toolchain): Update NDK to r29

[fornwall]

See the r29 changelog - mostly a LLVM bump.

Known TODO:s

• The swift-specific C++ patches in ndk-patches/28c/c++-v1-module.modulemap.patch and ndk-patches/28c/c++-v1-stdlib.h.patch no longer applied and has been temporarily removed.
  • @finagolfin Can you have a look with adding the patches and test them?
• Build more packages (have tested some random packages quickly, like imagemagick/dpkg/apt/bash/readline/ncurses/git/openssl/gtk4/qt6-qtbase/libgnutls/libllvm/rust/cmake/openssh/tmux/zsh/bash/python/python-numpy/perl/ruby/grep/ripgrep/postgresql/openssl/ffmpeg/imagemagick/tmux/weechat, and they all built fine without patches necessary).
• Some on-device testing (have not done that yet).

[robertkirkman]

The TERMUX_PKG_SHA256 and some other content in these build.sh files is outdated/broken and doesn't currently work if TERMUX_ON_DEVICE_BUILD is true.

I have a PR here which fixes that,

• fix(ndk): fix on-device building and remove custom __ANDROID_API__ header patches #25786

however, the reason I didn't merge my PR yet is because,

I wanted some more feedback from the two users who are currently known to be actually affected by the errors the outdated build.sh content causes, about what priorities they have so I could try to orient any further changes towards their needs, but unfortunately neither of them have responded yet, in their issues:

• [Bug]: clang cannot compile for api levels other than default #23401
• [Bug]: libc++ download error #26838

Do you think I should go ahead and merge that PR before you merge this one, or would you want to copy the changes from it to this PR, or should I continue to hold off from merging it?

Other than any hypothetical requests that the users haven't asked for yet, the changes are ready.

[fornwall]

Do you think I should go ahead and merge that PR before you merge this one, or would you want to copy the changes from it to this PR, or should I continue to hold off from merging it?

Do what you think is best / easiest for you - this PR can be adapted later on if necessary!

[robertkirkman]

Ok, I will merge my PR in 24 hours, and then this PR can be rebased on it and I'll also test building this PR on-device after the rebase to make sure that its changes which work for NDK r28c also work for NDK r29.

[robertkirkman]

I have merged my PR now, which has caused this PR to have merge conflicts, but I hope it's not too much trouble to rebase this now.

[finagolfin]

The swift-specific C++ patches in ndk-patches/28c/c++-v1-module.modulemap.patch and ndk-patches/28c/c++-v1-stdlib.h.patch no longer applied and has been temporarily removed.
@finagolfin Can you have a look with adding the patches and test them?

OK, don't worry about it. I will bump Swift to 6.2 later this week and add back whatever I need then. 👍