Input sanitation. Minimum amount fix. Debug log updated.

backend/src/routes.ts

@@ -118,11 +118,21 @@ class Routes {
       return;
     }
 
+    if (p.orderId !== '' && !/^(@|)[a-zA-Z0-9_]{1,15}$/.test(p.orderId)) {
+      res.status(400).send('Invalid Twitter handle');
+      return;
+    }
+
     if (p.amount < 0.001) {
       res.status(400).send('Amount needs to be at least 0.001');
       return;
     }
 
+    if (p.amount > 1000) {
+      res.status(400).send('Amount too large');
+      return;
+    }
+
     try {
       const result = await donations.createRequest(p.amount, p.orderId);
       res.json(result);