feat(MED-99): use montonio api and webhook

packages/billing/montonio/src/schema/montonio-client-env.schema.ts

@@ -0,0 +1,6 @@
+import { z } from 'zod';
+
+export const MontonioClientEnvSchema = z
+  .object({
+    accessKey: z.string().min(1),
+  });

packages/billing/montonio/src/schema/montonio-server-env.schema.ts

@@ -0,0 +1,15 @@
+import { z } from 'zod';
+
+export const MontonioServerEnvSchema = z
+  .object({
+    secretKey: z
+      .string({
+        required_error: `Please provide the variable MONTONIO_SECRET_KEY`,
+      })
+      .min(1),
+    apiUrl: z
+      .string({
+        required_error: `Please provide the variable MONTONIO_API_URL`,
+      })
+      .min(1),
+  });