Bump workspace to edition 2024

- edition = "2024" in the workspace manifest and rsdosedit
- extern blocks must be unsafe: interrupts.rs ISR stubs -> unsafe extern "C"
- #[no_mangle] -> #[unsafe(no_mangle)] (efi_main, isr_dispatch)
- One missed static-mut read in free_list_insert wrapped in an explicit
  unsafe block (edition 2024 removed the implicit unsafe context inside
  unsafe fns)
- rustfmt reflows for 2024: nested if-lets become let-chains, imports
  re-sorted, rsdosedit help-screen box rows wrapped

No codegen-affecting changes. Validated: cargo check/clippy/fmt clean
(host + uefi target), make test-disk PASS, editor round-trip PASS.

1 files changed, 1 insertions, 1 deletions

diff --git a/rsnix/src/power.rs b/rsnix/src/power.rs
index cb5d296..3ca0f25 100644
--- a/rsnix/src/power.rs
+++ b/rsnix/src/power.rs
@@ -9,7 +9,7 @@
 // QEMU this makes the VM exit, on real hardware the power drops.
 // ---------------------------------------------------------------------------
 
-use crate::uefi::{RuntimeServices, EFI_SUCCESS, RESET_SHUTDOWN};
+use crate::uefi::{EFI_SUCCESS, RESET_SHUTDOWN, RuntimeServices};
 
 static mut RUNTIME_SERVICES: *mut RuntimeServices = core::ptr::null_mut();