fix: use #include_next in Linux overlay shims to prevent infinite recursion

All 6 case-sensitivity shim headers in tools/linux/overlay/include/
now use #include_next instead of #include to forward to the real
MinGW system header, avoiding infinite preprocessor recursion on
Linux (Debian/WSL) where overlay/include is first in the search path.

Fixes build failures on Debian WSL (GCC 12) for all configurations.
Also update nsis7z.dll binaries built with the fixed overlay.

tools/linux/overlay/include/CommCtrl.h

@@ -1,3 +1,5 @@
-/* Linux/MinGW cross-build shim: CommCtrl.h → commctrl.h */
+/* Linux/MinGW cross-build shim: CommCtrl.h → commctrl.h
+ * Uses #include_next so this shim is skipped on the recursive search,
+ * forwarding to the real MinGW system commctrl.h without infinite recursion. */
 #pragma GCC system_header
-#include <commctrl.h>
+#include_next <commctrl.h>

tools/linux/overlay/include/MAPI.h

@@ -1,3 +1,5 @@
-/* Linux/MinGW cross-build shim: MAPI.h → mapi.h */
+/* Linux/MinGW cross-build shim: MAPI.h → mapi.h
+ * Uses #include_next so this shim is skipped on the recursive search,
+ * forwarding to the real MinGW system mapi.h without infinite recursion. */
 #pragma GCC system_header
-#include <mapi.h>
+#include_next <mapi.h>

tools/linux/overlay/include/NTSecAPI.h

@@ -1,3 +1,5 @@
-/* Linux/MinGW cross-build shim: NTSecAPI.h → ntsecapi.h */
+/* Linux/MinGW cross-build shim: NTSecAPI.h → ntsecapi.h
+ * Uses #include_next so this shim is skipped on the recursive search,
+ * forwarding to the real MinGW system ntsecapi.h without infinite recursion. */
 #pragma GCC system_header
-#include <ntsecapi.h>
+#include_next <ntsecapi.h>

tools/linux/overlay/include/Psapi.h

@@ -1,3 +1,5 @@
-/* Linux/MinGW cross-build shim: Psapi.h → psapi.h */
+/* Linux/MinGW cross-build shim: Psapi.h → psapi.h
+ * Uses #include_next so this shim is skipped on the recursive search,
+ * forwarding to the real MinGW system psapi.h without infinite recursion. */
 #pragma GCC system_header
-#include <psapi.h>
+#include_next <psapi.h>

tools/linux/overlay/include/ShlObj.h

@@ -1,3 +1,5 @@
-/* Linux/MinGW cross-build shim: ShlObj.h → shlobj.h */
+/* Linux/MinGW cross-build shim: ShlObj.h → shlobj.h
+ * Uses #include_next so this shim is skipped on the recursive search,
+ * forwarding to the real MinGW system shlobj.h without infinite recursion. */
 #pragma GCC system_header
-#include <shlobj.h>
+#include_next <shlobj.h>

tools/linux/overlay/include/Windows.h

@@ -1,3 +1,5 @@
-/* Linux/MinGW cross-build shim: Windows.h → windows.h */
+/* Linux/MinGW cross-build shim: Windows.h → windows.h
+ * Uses #include_next so this shim is skipped on the recursive search,
+ * forwarding to the real MinGW system windows.h without infinite recursion. */
 #pragma GCC system_header
-#include <windows.h>
+#include_next <windows.h>