feat(baserow): add one-time SSO warning JavaScript

- Introduced a generic sso_warning.js.j2 template under
  templates/roles/web-app/templates/javascripts/
- Included this template in web-app-baserow/templates/javascript.js.j2
- Added new variable js_application_name in
  roles/web-app-baserow/vars/main.yml to make the warning
  application-specific
- Implemented cookie-based logic so the warning is only shown once
  per user (default: 365 days)

Reference: https://chatgpt.com/share/68aecdae-82d0-800f-b05e-f2cb680664f1

templates/roles/web-app/templates/javascripts/sso_warning.js.j2

@@ -0,0 +1,34 @@
+// Jinja2 variable for the application name
+const appName = "{{ js_application_name }}";
+const cookieName = appName + "SSONoticeShown";
+
+// Function to set a cookie with expiration (in days)
+function setCookie(name, value, days) {
+    const d = new Date();
+    d.setTime(d.getTime() + (days*24*60*60*1000));
+    const expires = "expires="+ d.toUTCString();
+    document.cookie = name + "=" + value + ";" + expires + ";path=/";
+}
+
+// Function to read a cookie
+function getCookie(name) {
+    const cname = name + "=";
+    const decodedCookie = decodeURIComponent(document.cookie);
+    const ca = decodedCookie.split(';');
+    for(let i = 0; i < ca.length; i++) {
+        let c = ca[i].trim();
+        if (c.indexOf(cname) === 0) {
+            return c.substring(cname.length, c.length);
+        }
+    }
+    return "";
+}
+
+// Main logic: show notice only once
+window.addEventListener("DOMContentLoaded", function() {
+    if (!getCookie(cookieName)) {
+        alert("Notice: " + appName + " is not integrated into the SSO. Login is not possible.");
+        // Set cookie for 365 days
+        setCookie(cookieName, "true", 365);
+    }
+});