feat: add upgrade banner for SLA feature (#9240)

- Add an upgrade CTA for the SLA feature

-------------------

Co-authored-by: Sojan Jose <sojan@pepalo.com>
Co-authored-by: Pranav <pranav@chatwoot.com>

app/javascript/dashboard/i18n/locale/en/sla.json

@@ -6,6 +6,17 @@
     "DESCRIPTION": "Service Level Agreements (SLAs) are contracts that define clear expectations between your team and customers. They establish standards for response and resolution times, creating a framework for accountability and ensures a consistent, high-quality experience.",
     "LEARN_MORE": "Learn more about SLA",
     "LOADING": "Fetching SLAs",
+    "PAYWALL": {
+      "TITLE": "Upgrade to create SLAs",
+      "AVAILABLE_ON": "The SLA feature is only available in the Business and Enterprise plans.",
+      "UPGRADE_PROMPT": "Upgrade your plan to get access to advanced features like team management, automations, custom attributes, and more.",
+      "UPGRADE_NOW": "Upgrade now"
+    },
+    "ENTERPRISE_PAYWALL": {
+      "AVAILABLE_ON": "The SLA feature is only available in the paid plans.",
+      "UPGRADE_PROMPT": "Upgrade to a paid plan to access advanced features like audit logs, agent capacity, and more.",
+      "ASK_ADMIN": "Please reach out to your administrator for the upgrade."
+    },
     "LIST": {
       "404": "There are no SLAs available in this account.",
       "EMPTY": {