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/sbc_request_trace.rs

@@ -367,7 +367,7 @@ unsafe fn worker() {
     }
     let mut base = 0usize;
     for _ in 0..600u32 {
-        base = GetModuleHandleA(b"CardsDLL_Win64_retail.dll\0".as_ptr()) as usize;
+        base = GetModuleHandleA(c"CardsDLL_Win64_retail.dll".as_ptr().cast()) as usize;
         if base != 0 {
             break;
         }