feat(workflow): automate Jira summary pipeline with optional Xray/Sonar links and solution version

- add npm workflow to fetch recent Jira issues, summarize them, and create a target Jira ticket
- generate HTML report and optional SMTP email output
- add Docker runtime and TeamCity runner scripts (sh/ps1)
- support optional SOLUTION_VERSION, XRAY_REPORT_URL, SONAR_REPORT_URL
- map SOLUTION_VERSION to Jira fixVersions on ticket creation
- update README and .env.example with new configuration

src/email.js

@@ -0,0 +1,44 @@
+const nodemailer = require("nodemailer");
+
+async function sendReportMail({ smtpConfig, subject, html, text }) {
+  if (!smtpConfig.enabled) {
+    return { skipped: true, reason: "SMTP_ENABLED=false" };
+  }
+
+  if (
+    !smtpConfig.host ||
+    !smtpConfig.port ||
+    !smtpConfig.user ||
+    !smtpConfig.pass ||
+    !smtpConfig.from ||
+    smtpConfig.to.length === 0
+  ) {
+    throw new Error(
+      "SMTP ist aktiviert, aber SMTP_HOST/PORT/USER/PASS/FROM/TO sind nicht vollstaendig gesetzt."
+    );
+  }
+
+  const transport = nodemailer.createTransport({
+    host: smtpConfig.host,
+    port: smtpConfig.port,
+    secure: smtpConfig.secure,
+    auth: {
+      user: smtpConfig.user,
+      pass: smtpConfig.pass,
+    },
+  });
+
+  const info = await transport.sendMail({
+    from: smtpConfig.from,
+    to: smtpConfig.to.join(", "),
+    subject,
+    text,
+    html,
+  });
+
+  return { skipped: false, messageId: info.messageId };
+}
+
+module.exports = {
+  sendReportMail,
+};