[FIX] mail: clean chat window thread avatar

Remove uncessary ThreadIcon that only served as spacing, properly add
module icon for chatter records.

closes odoo/odoo#125388

Signed-off-by: Sébastien Theys (seb) <seb@odoo.com>

addons/mail/static/src/core/common/chat_window.xml

@@ -17,12 +17,9 @@
             <div t-if="ui.isSmall" class="cursor-pointer d-flex align-items-center h-100 px-3 py-0 me-2" title="Close conversation" t-on-click="() => this.close()">
                 <i class="oi oi-arrow-left"/>
             </div>
-            <div t-if="thread and thread.model === 'discuss.channel'" class="o-mail-ChatWindow-threadAvatar my-0" t-att-class="{ 'ms-3': !ui.isSmall, 'me-1': thread.type === 'chat', 'me-3': thread.type !== 'chat' }">
+            <div t-if="thread" class="o-mail-ChatWindow-threadAvatar my-0" t-att-class="{ 'ms-3': !ui.isSmall, 'me-1': thread.type === 'chat', 'me-3': thread.type !== 'chat' }">
                 <img class="rounded" t-att-src="thread.imgUrl" alt="Thread Image"/>
             </div>
-            <t t-else="">
-                <ThreadIcon t-if="thread" thread="thread" className="'ms-3 me-1 my-0'"/>
-            </t>
             <ThreadIcon t-if="thread and thread.type === 'chat' and thread.correspondent" thread="thread" className="'me-1'"/>
             <span class="o-mail-ChatWindow-name text-truncate fw-bold" t-att-title="props.chatWindow.displayName" t-esc="props.chatWindow.displayName" t-att-class="{
                     'ms-3 me-1 my-0': !thread,

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

@@ -240,10 +240,13 @@ export class MessageService {
             linkPreviews = message.linkPreviews,
             message_type: type = message.type,
             model: resModel = message.resModel,
+            module_icon,
             notifications = message.notifications,
             parentMessage,
             recipients = message.recipients,
+            record_name,
             res_id: resId = message.resId,
+            res_model_name,
             subtype_description: subtypeDescription = message.subtypeDescription,
             ...remainingData
         } = data;
@@ -263,11 +266,12 @@ export class MessageService {
             type,
         });
         // origin thread before other information (in particular notification insert uses it)
-        if (data.record_name) {
-            message.originThread.name = data.record_name;
-        }
-        if (data.res_model_name) {
-            message.originThread.modelName = data.res_model_name;
+        if (message.originThread) {
+            assignDefined(message.originThread, {
+                modelName: res_model_name || undefined,
+                module_icon: module_icon || undefined,
+                name: record_name || undefined,
+            });
         }
         replaceArrayWithCompare(
             message.attachments,

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

@@ -76,6 +76,10 @@ export class Thread {
      * @type {import("@mail/core/common/message_model").Message[]}
      */
     messages = [];
+    /** @type {string} */
+    modelName;
+    /** @type {string} */
+    module_icon;
     /**
      * Contains messages received from the bus that are not yet inserted in
      * `messages` list. This is a temporary storage to ensure nothing is lost
@@ -251,9 +255,7 @@ export class Thread {
     }
 
     get imgUrl() {
-        return (
-            this.newestNeedactionMessage?.module_icon ?? "/mail/static/src/img/smiley/avatar.jpg"
-        );
+        return this.module_icon ?? "/mail/static/src/img/smiley/avatar.jpg";
     }
 
     get allowDescription() {