Assert that params with the same *index* have the same *name*

Found this bug when trying to build libcore with the new solver, since it will canonicalize two params with the same index into *different* placeholders if those params differ by name.

…iaskrgr

Rollup of 9 pull requests

Successful merges:

 - rust-lang#113833 (`std::error::Error` -> Trait Implementations: lifetimes consistency improvement)
 - rust-lang#115386 (PartialEq, PartialOrd: update and synchronize handling of transitive chains)
 - rust-lang#116284 (make matching on NaN a hard error, and remove the rest of illegal_floating_point_literal_pattern)
 - rust-lang#118960 (Add LocalWaker and ContextBuilder types to core, and LocalWake trait to alloc.)
 - rust-lang#120384 (Use `<T, U>` for array/slice equality `impl`s)
 - rust-lang#120518 (riscv only supports split_debuginfo=off for now)
 - rust-lang#120619 (Assert that params with the same *index* have the same *name*)
 - rust-lang#120657 (Remove unused struct)
 - rust-lang#120661 (target: default to the medium code model on LoongArch targets)

r? `@ghost`
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