Auto merge of #122565 - Zoxc:atomic-panic-msg, r=the8472

Try to write the panic message with a single `write_all` call

This writes the panic message to a buffer before writing to stderr. This allows it to be printed with a single `write_all` call, preventing it from being interleaved with other outputs. It also adds newlines before and after the message ensuring that only the panic message will have its own lines.

Before:
```
thread 'thread 'thread 'thread 'thread '<unnamed>thread 'thread 'thread 'thread '<unnamed><unnamed>thread '<unnamed>' panicked at ' panicked at <unnamed><unnamed><unnamed><unnamed><unnamed>' panicked at <unnamed>' panicked at src\heap.rssrc\heap.rs'
panicked at ' panicked at ' panicked at ' panicked at ' panicked at src\heap.rs' panicked at src\heap.rs::src\heap.rssrc\heap.rssrc\heap.rssrc\heap.rssrc\heap.rs:src\heap.rs:455455:::::455:455::455455455455455:455:99:::::9:9:
:
999:
999:
assertion failed: size <= (*queue).block_size:
:
assertion failed: size <= (*queue).block_size:
assertion failed: size <= (*queue).block_size:
:
:
assertion failed: size <= (*queue).block_sizeassertion failed: size <= (*queue).block_sizeassertion failed: size <= (*queue).block_size

assertion failed: size <= (*queue).block_size
assertion failed: size <= (*queue).block_sizeassertion failed: size <= (*queue).block_sizeerror: process didn't exit successfully: `target\debug\direct_test.exe` (exit code: 0xc0000409, STATUS_STACK_BUFFER_OVERRUN)
```
After:
```

thread '<unnamed>' panicked at src\heap.rs:455:9:
assertion failed: size <= (*queue).block_size

thread '<unnamed>' panicked at src\heap.rs:455:9:
assertion failed: size <= (*queue).block_size

thread '<unnamed>' panicked at src\heap.rs:455:9:
assertion failed: size <= (*queue).block_size

error: process didn't exit successfully: `target\debug\direct_test.exe` (exit code: 0xc0000409, STATUS_STACK_BUFFER_OVERRUN)
```

---

try-jobs: x86_64-gnu-llvm-18

0 files changed, 0 insertions, 0 deletions