[FIX] mail, im_livechat: fix perf of thread sorting

Make correspondent a compute to benefit from cache.

This reduces the time on populate medium from around 600ms to 200ms.

closes odoo/odoo#146109

Related: odoo/enterprise#52703
Signed-off-by: Alexandre Kühn (aku) <aku@odoo.com>

addons/im_livechat/static/src/core/web/thread_model_patch.js

@@ -25,8 +25,8 @@ patch(Thread.prototype, {
         return super.correspondents.filter((correspondent) => !correspondent.is_bot);
     },
 
-    get correspondent() {
-        let correspondent = super.correspondent;
+    computeCorrespondent() {
+        let correspondent = super.computeCorrespondent();
         if (this.type === "livechat" && !correspondent) {
             // For livechat threads, the correspondent is the first
             // channel member that is not the operator.

addons/mail/static/src/core/common/thread_model.js

@@ -186,6 +186,11 @@ export class Thread extends Record {
     invitedMembers = Record.many("ChannelMember");
     chatPartner = Record.one("Persona");
     composer = Record.one("Composer", { inverse: "thread", onDelete: (r) => r.delete() });
+    correspondent2 = Record.one("Persona", {
+        compute() {
+            return this.computeCorrespondent();
+        },
+    });
     counter = 0;
     /** @type {string} */
     custom_channel_name;
@@ -360,8 +365,11 @@ export class Thread extends Record {
             .filter((p) => p.notEq(this._store.self));
     }
 
-    /** @type {import("models").Persona|undefined} */
     get correspondent() {
+        return this.correspondent2;
+    }
+
+    computeCorrespondent() {
         if (this.type === "channel") {
             return undefined;
         }