build: switch from yarn to npm to manage js dependencies and move js contents to root

yarn v1 is being deprecated and starts to have some issues

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

src/types/paginate.ts

@@ -0,0 +1,4 @@
+export interface Paginate<T> {
+  elements: T[];
+  total: number;
+}