feat(medusa): Implement premises of the creation flow of an order edit (#2187)

**What**
- Implements the admin create end point 
- Service implementation of the create method and the retrieveActive as well as the totals computation
- Improve compute line items
- client
  - medusa-js api
  - medusa-react mutations hooks

**Tests**
- Unit tests of the create end points
- Unit tests of the service create method
- Integration tests for admin that also take into account totals computations
- client
  - medusa-js tests
  - medusa-react hooks tests

FIXES CORE-491

packages/medusa-react/mocks/handlers/admin.ts

@@ -1664,6 +1664,18 @@ export const adminHandlers = [
     )
   }),
 
+  rest.post("/admin/order-edits/", (req, res, ctx) => {
+    return res(
+      ctx.status(200),
+      ctx.json({
+        order_edit: {
+          ...fixtures.get("order_edit"),
+          ...(req.body as any),
+        },
+      })
+    )
+  }),
+
   rest.get("/store/order-edits/:id", (req, res, ctx) => {
     const { id } = req.params
     return res(