refactor(structure): normalize folder names with leading zeros for consistency

- Renamed all folders from format NEx (e.g., 1Ex, 2Ex...) to 0NEx (01Ex, 02Ex, etc.)
- Updated subdirectories and files accordingly
- Removed old main Makefile and tasks (a01.c–a09.c, solve.c, io_status.h), likely obsolete
- Cleaned up deprecated task binaries and configs

2025.03.07/02Ex/solve.h

@@ -0,0 +1,6 @@
+#ifndef SOLVE_H
+#define SOLVE_H
+
+double t2_solve(double *a, int n);
+
+#endif