Rollup of 12 pull requests

Successful merges:

 - #142205 (Mark `slice::swap_with_slice` unstably const)
 - #144188 (`available_parallelism`: Add documentation for why we don't look at `ulimit`)
 - #144322 (Add lint against dangling pointers from local variables)
 - #144497 (tests: Add test for basic line-by-line stepping in a debugger)
 - #144559 (Enable extract-insert-dyn.rs test on RISC-V (riscv64))
 - #144667 (`AlignmentEnum` should just be `repr(usize)` now)
 - #144706 (Do not give function allocations alignment in consteval and Miri.)
 - #144746 (resolve: Cleanups and micro-optimizations to extern prelude)
 - #144785 (Regression test for LLVM error with unsupported expression in static initializer for const pointer in array on macOS.)
 - #144811 (Stylize `*-lynxos178-*` target maintainer handle to make it easier to copy/paste)
 - #144848 (For "stage 1" ui-fulldeps, use the stage 1 compiler to query target info)
 - #144853 (Remove unnecessary `rust_` prefixes)

Failed merges:

 - #144794 (Port `#[coroutine]` to the new attribute system)

r? `@ghost`
`@rustbot` modify labels: rollup

Rollup merge of #144848 - Zalathar:ui-fulldeps, r=clubby789

For "stage 1" ui-fulldeps, use the stage 1 compiler to query target info

Testing ui-fulldeps in "stage 1" actually uses the stage 0 compiler, so that test programs can link against stage 1 rustc crates.

Unfortunately, using the stage 0 compiler causes problems when compiletest tries to obtain target information from the compiler, but the output format has changed since the last bootstrap beta bump.

We can work around this by also providing compiletest with a stage 1 compiler, and having it use that compiler to query for target information.

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This fixes the stage 1 ui-fulldeps failure seen at #144443 (comment).