Rollup of 7 pull requests

[Centril]

Successful merges:

• Fix zero-size uninitialized boxes #65174 (Fix zero-size uninitialized boxes)
• ci: move most of the prepare config into scripts #65202 (ci: move most of the prepare config into scripts)
• build-std compatible sanitizer support #65241 (build-std compatible sanitizer support)
• Update libc to 0.2.64 #65469 (Update libc to 0.2.64)
• Suppress ICE when validators disagree on LiveDrops in presence of &mut #65485 (Suppress ICE when validators disagree on LiveDrops in presence of &mut)
• Refer to "associated functions" instead of "static methods" #65542 (Refer to "associated functions" instead of "static methods")
• More symbol cleanups #65545 (More symbol cleanups)

Failed merges:

• Add long error explanation for E0577 #65434 (Add long error explanation for E0577)
• Add long error explanation for E0578 #65471 (Add long error explanation for E0578)
• Remove src/llvm-emscripten submodule #65501 (Remove src/llvm-emscripten submodule)

r? @ghost