Add peer type resolution for compatible tuples and arrays

[PastMoments]

Fixes #15138.

Adds Peer Type Resolution between tuples and arrays, where the tuple can coerce into the array.

[PastMoments]

Sorry if anyone was waiting on this.

The summary is that i was using the wrong version of zig fmt mistakenly, and then got distracted trying to update to llvm 16.

Those issues (should) be fixed now.

[PastMoments]

Actually, looks like the rework in #15726 will resolve this issue, so I'm going to close this PR.

[PastMoments]

For anyone that happens to stumble on this and has the same issue that I do (pacman hasn't updated to llvm 16 yet). Here's how to compile and use llvm 16 (I copied this from edtoml in some AUR comment).

cd ~/llvm
git clone --depth 1 --branch release/16.x https://github.com/llvm/llvm-project llvm-project-16
cd llvm-project-16
git checkout release/16.x
mkdir build
cd build
cmake ../llvm \
  -DCMAKE_INSTALL_PREFIX=$HOME/local/llvm16 \
  -DCMAKE_PREFIX_PATH=$HOME/local/llvm16 \
  -DCMAKE_BUILD_TYPE=Release \
  -DLLVM_ENABLE_PROJECTS="lld;clang" \
  -DLLVM_ENABLE_LIBXML2=OFF \
  -DLLVM_ENABLE_TERMINFO=OFF \
  -DLLVM_ENABLE_LIBEDIT=OFF \
  -DLLVM_ENABLE_ASSERTIONS=ON \
  -G Ninja \
  -DLLVM_PARALLEL_LINK_JOBS=1 \
  -DLLVM_ENABLE_BINDINGS=OFF
ninja install

then set the environment variable
PATH=$HOME/local/llvm16/bin:$PATH