Crash reports and a guard for burning bone particles without a device

- re/crash: unhandled exceptions write sacred_re_crash.txt (module+offset,
  registers, return addresses on the stack) and a minidump; the game's own
  filter is chained behind ours
- guards: cParticleSystem_burningBone::Render (0x774e10) skips drawing when
  given a null device (crash at sacred.exe+0x374e39 after Esc while walking)

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

src/mods/guards.cpp

@@ -0,0 +1,30 @@
+// Guards against crashes in the game's own code (each with what is known of
+// its cause).
+
+#include <intrin.h>
+
+#include "re/hook.h"
+#include "re/log.h"
+
+namespace game {
+
+// cParticleSystem_burningBone::Render (vf04 0x774e10, vtable 0x895b84):
+// crashed reading the device it was given, which was null (2026-10-16, Esc
+// pressed while walking; Windows reported sacred.exe+0x374e39). Who renders
+// it without a device is not known yet (sacred_re_crash.txt will tell). With
+// no device there is nothing to draw.
+void __fastcall BurningBone_Render(void* self, void* edx, void* device);
+RE_HOOK(0x00774e10, BurningBone_Render);
+void __fastcall BurningBone_Render(void* self, void* edx, void* device) {
+    if (!device) {
+        static bool logged = false;
+        if (!logged) {
+            logged = true;
+            re::Log("guards: burning bone particles rendered without a device, skipped (%p)", _ReturnAddress());
+        }
+        return;
+    }
+    BurningBone_Render_original(self, edx, device);
+}
+
+} // namespace game