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 #144559 - CaiWeiran:extract-insert-dyn_test, r=Mark-Simulacrum

Enable extract-insert-dyn.rs test on RISC-V (riscv64)

This PR adds support for running the `tests/codegen-llvm/simd/extract-insert-dyn.rs` test on the RISC-V (riscv64) architecture.

Previously, this test would fail on RISC-V targets due to architecture-specific code generation issues. This patch modifies the test to ensure compatibility while preserving its intent.

The change has been tested locally using `./x test` on a riscv64 target, and the test now passes as expected.

### Notes:
- This change is scoped specifically to improve RISC-V compatibility.
- It does not affect behavior or test results on other architectures.

Rollup of 12 pull requests

Successful merges:

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

Failed merges:

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

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