feat: complete saleor core extensions app with React email templates

- Order confirmation, shipped, and cancelled email templates
- Uses @react-email/components for professional HTML emails
- Sends admin and customer notifications
- Integrates with Resend for email delivery
- Webhook handlers for ORDER_CREATED, ORDER_FULFILLED, ORDER_CANCELLED
- Docker image optimized for production
- Persistent auth data storage via PVC

.github/scripts/open-prod-pr.mjs

@@ -0,0 +1,46 @@
+import { spawnSync } from "node:child_process";
+
+const {
+  stdout: branchesDiffer,
+  stderr,
+  status,
+} = spawnSync("git", ["log", "main..canary"], {
+  encoding: "utf8",
+});
+
+if (status !== 0) {
+  console.error("Fail reading branches diff");
+  console.error(stderr);
+  process.exit(1);
+}
+
+if (branchesDiffer === "") {
+  console.log("Branches canary and main have no different commits");
+  process.exit(0);
+} else if (branchesDiffer.length > 0) {
+  const result = spawnSync(
+    "gh",
+    [
+      "pr",
+      "create",
+      "-B",
+      "main",
+      "-H",
+      "canary",
+      "--title",
+      "Merge canary to main",
+      "--body",
+      "Merge canary to main, to trigger a prod release",
+    ],
+    {}
+  );
+
+  if (result.status === 0) {
+    console.log("Successfully opened a PR");
+    process.exit(0);
+  } else {
+    console.error("Error trying to open a PR");
+    console.error(result.stderr);
+    process.exit(1);
+  }
+}