fix: repair pipeline and use curtle.h

.gitea/workflows/ci.yml

@@ -10,7 +10,7 @@ jobs:
       - uses: actions/checkout@v3
 
       - name: install deps
-        run: sudo apt install cmake
+        run: apt install cmake
 
       - name: build
         run: |

include/curtle/curtle.h

@@ -0,0 +1,6 @@
+#ifndef CURTLE_H
+#define CURTLE_H
+
+#include "curtle/linear_algebra.h"
+
+#endif