Add Task as a builtin module/type

[lukewilliamboswell]

This is a twin PR for roc-lang/roc#6836 in the roc-lang/roc repo.

It updates the FFI in this platform to return exclusively Tasks, as well as removes this platform's Task module (and InternalTask).

[lukewilliamboswell]

Rebased on main, and updated to use latest roc-lang/roc branch.

Currently fails with the following;

$ ROC=roc EXAMPLES_DIR=examples/ bash ci/all_tests.sh
<------SNIP------>
++ uname -m
+ architecture=arm64
+ for roc_file in '$EXAMPLES_DIR*.roc'
+ roc build --prebuilt-platform --linker=legacy examples/command.roc
0 errors and 0 warnings found in 260 ms
 while successfully building:

    examples/command
+ for roc_file in '$EXAMPLES_DIR*.roc'
+ roc build --prebuilt-platform --linker=legacy examples/dir.roc
thread 'main' panicked at /Users/luke/.cargo/git/checkouts/inkwell-55729a4c43239568/d1a5963/src/values/enums.rs:302:13:
Found StructValue(StructValue { struct_value: Value { name: "load_result", address: 0x600000866900, is_const: false, is_null: false, is_undef: false, llvm_value: "  %load_result = load { [0 x i64], [3 x i64], i8, [7 x i8] }, ptr %result_value, align 8, !dbg !10", llvm_type: "{ [0 x i64], [3 x i64], i8, [7 x i8] }" } }) but expected PointerValue variant
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

[Anton-4]

I apologize for the many commits, I'm currently on Ubuntu and it's easiest to make all the changes using the github website.

[Anton-4]

Right, backpassing is deprecated now, need to update some code...

[Anton-4]

I'm going to try to make an llm perform all the backpassing changes :p

[smores56]

I'll clean this up now!

[smores56]

Not much was really needed, we are now just waiting for a basic-cli v0.15 release to update our scripts with, then we can merge this