feat: stabilize API startup and lifecycle management

- Refactor server initialization to separate concerns and improve error handling.
- Implement centralized environment validation using Zod.
- Introduce database, Redis, and queue lifecycle management.
- Add health check endpoints for liveness and readiness.
- Enhance error handling middleware for better response structure.
- Implement rate limiting for API endpoints.
- Add request ID middleware for traceability.
- Create Sequelize CLI configuration and baseline migration for schema management.
- Establish CI workflow with Gitea for testing and syntax checks.
- Document foundational changes and migration strategy in PHASE_0_FOUNDATION_STABILIZATION.md.
- Add Docker Compose configuration for local development and testing.
- Implement unit and integration tests for critical functionality.

app/utils/mail.util.js

@@ -23,10 +23,12 @@ const transporter = nodemailer.createTransport({
   auth: mailConfig.auth,
 });
 
-transporter.verify((err) => {
-  if (err) console.error("Mail server connection failed", err);
-  else console.log("Mail server ready");
-});
+if (process.env.NODE_ENV !== "test" && process.env.ENABLE_MAIL === "true") {
+  transporter.verify((err) => {
+    if (err) console.error("Mail server connection failed", { message: err.message });
+    else console.log("Mail server ready");
+  });
+}
 
 // Utility to load template and replace placeholders
 const loadTemplate = (templateName, variables = {}) => {
@@ -42,6 +44,9 @@ const loadTemplate = (templateName, variables = {}) => {
 };
 
 const send = async ({ to, subject, templateName, templateVars = {}, text }) => {
+  if (process.env.ENABLE_MAIL !== "true") {
+    throw new Error("Email functionality is not enabled");
+  }
   const html = templateName ? loadTemplate(templateName, templateVars) : undefined;
 
   const mailOptions = {