feat: make userspace StatusCodes positive; print status text along with code in shell exec; make init return BadInvocation on faulty launch

programs/src/shell/exec.cpp

@@ -17,7 +17,9 @@ static bool file_exists(const char* path) {
 
 // ---- Try to spawn an ELF at the given path ----
 
-static void print_exit_code(int code) {
+static void print_exit_code(const int exitCode) {
+    int code = exitCode;
+
     if (code == 0) return;
     char buf[16];
     int n = 0;
@@ -36,6 +38,16 @@ static void print_exit_code(int code) {
         char c[2] = { buf[--n], 0 };
         montauk::print(c);
     }
+    
+    if (exitCode > 0 && exitCode <= 14) { // 0-14 - current range of status codes within StatusCodes enum
+        const char* statusText = montauk::GetStatusText((montauk::StatusCodes)exitCode);
+        
+        if (statusText != nullptr) {
+            montauk::print(" - ");
+            montauk::print(statusText);
+        }
+    }
+
     montauk::print("]\n");
 }