Update to a newer nightly

[LegNeato]

We need to update to as new of a nightly as possible. The current nightly is extremely old. At the very least, we need to update past a nightly that fixes #29. Unfortunately, there are some hard breaks from rustc in the update that we'll have to do substantial work to port past. Specifically, these untyped alloc changes: rust-lang/rust@f4426c1

[LegNeato]

@eddyb is already working on this but I wanted to get a task written so people know it is coming 🚀

[LegNeato]

When this lands, we should turn on Mac dev builds (see #52)

[eddyb]

Current status: nightly-2024-11-22 (~1.84) achieved by:

• Hack around blockers to update toolchain all the way to nightly-2024-11-22 (~1.84). #170

At the cost of having to eventually deal with those hacks:

• Tracking issue: undo rustc_codegen_ssa patching (aka pqp_cg_ssa). #182