implement user mode catchable exceptions, refactor system status codes to use NTLSTATUS_ prefix, update build scripts to use shared literal macros for linker arguments, update named queue lifetime cleanup to include KeNamedQueueUnpublishHandle.

code/user/runtime/native_start.c

@@ -0,0 +1,18 @@
+// Native process startup. This file owns process-local native runtime initialization before main runs.
+
+#include <stdint.h>
+#include <ntlite/exception.h>
+#include <ntlite/syscall.h>
+
+extern int main(void);
+
+// Initializes native process state and exits with main's return value.
+void NtlNativeStart(void) {
+    uint32_t status = NtlInitializeExceptionRuntime();
+    if (status != NTLSTATUS_SUCCESS) {
+        for (;;) SysExitProcess((int32_t)status);
+    }
+
+    int exitCode = main();
+    for (;;) SysExitProcess(exitCode);
+}