style(hook): clippy -D warnings clean on default + fifa17 features

Modernize manual nul-terminated byte strings to C-string literals (c"...")
at all Win32 GetModuleHandleA/GetProcAddress/getaddrinfo call sites (byte-identical),
drop two redundant SOL_SOCKET-as-i32 casts, remove a needless return in the fifa17
install path, and add a # Safety section to DllMain. Scope the FIFA-23-path
dead-code/unused-import lints (unused only under the fifa17 feature, stripped by the
linker) with a documented crate-level cfg_attr allow. Cross-verified: both the
default and fifa17 builds now pass clippy -D warnings and compile; probe and
capture_baseline still build.

openfut-hook/src/hooks.rs

@@ -71,7 +71,7 @@ pub unsafe extern "system" fn hooked_getaddrinfo(
                 let redirect = REDIRECT_IP
                     .get()
                     .map(|v| v.as_ptr())
-                    .unwrap_or(b"127.0.0.1\0".as_ptr());
+                    .unwrap_or(c"127.0.0.1".as_ptr().cast());
                 let real = REAL.get().copied().unwrap_or(sys_getaddrinfo);
                 return real(redirect, service_name, hints, result);
             }