general update, updated cimport so it parses struct definitions from imported headers, improved the error reporting, added ifdef and ifndef, added proper support for extern variadic functions, added some new sections and pages to the doc tool and added --check to only check the program corectness and run compile time defs without producing a binary

tests/error_recovery.sl

@@ -0,0 +1,15 @@
+# This file intentionally has multiple errors to test error recovery.
+# The compiler should report all of them rather than stopping at the first.
+# No stdlib import — keeps line numbers stable.
+
+word foo
+    end end
+end
+
+word bar
+    end end
+end
+
+word main
+    0
+end