fix(core): do not latch speedhack installed after a failed attach

[ResurrectedTrader]

Two small correctness issues in core, both found while auditing the hooking layer. Neither fires today; both are traps for the next caller.

speedhack::Install latched its flag on a failed attach

bool expected = false;
if (!isInstalled.compare_exchange_strong(expected, true)) {
    return;
}
if (const int32_t err = detour::AttachAll(HOOKS); err != 0) {
    Log().error(...);          // flag stays true
}

The flag is claimed before the attach. AttachAll is all-or-nothing — a failed commit has Detours roll every rewritten pointer back, so nothing is installed — but the flag then said otherwise. Two consequences:

• Remove() passes its own CAS and calls DetachAll on eighteen slots that were never attached.
• Any later Install() returns immediately, so the failure is permanent rather than retryable.

Now the flag is handed back on failure, so the state matches what is actually installed.

Nothing retries Install() today, so this is latent rather than a live bug.

Hook<Fn>'s Real() contract was wider than the code

The class comment claimed Real() reaches the original "whether or not the slot is attached". That is true for a slot built from an address — it has one from construction — but not for the other two constructors:

• Hook(Target::Export(...), replacement) has no address until an attach resolves the export.
• explicit Hook(Fn replacement) has no target at all until SetTarget.

In both cases Real() is null. The same applies after pointing a detached slot at an export, which drops the address it was holding — correctly, since the target moved and where is not known until the attach.

I narrowed the comment rather than widening the code. A slot that has not been told where its target lives has nothing truthful to return, and inventing a fallback would hide the mistake at the call site instead of surfacing it. Nothing calls Real() on an unresolved slot today.

Verification

clang-format clean, clang-tidy clean (118 files, full no-cache run), Win32 build 0 warnings / 0 errors.

🤖 Generated with Claude Code