[IMP] mail: introduce main and extra suggestions on composer view

Suggestion list view should depend on finding suggestables, not on the existence
of suggestion views (which themselves have to be computed on the suggestion list
view instead).

Part of task-2741982

Part-of: odoo/odoo#95341

addons/mail/static/src/models/composer_view.js

@@ -884,11 +884,21 @@ registerModel({
          * @private
          * @returns {FieldCommand}
          */
-        _computeExtraSuggestionViews() {
+        _computeExtraSuggestions() {
             if (this.suggestionDelimiterPosition === undefined) {
                 return clear();
             }
-            return unlink(this.mainSuggestionViews);
+            return unlink(this.mainSuggestions);
+        },
+        /**
+         * @returns {FieldCommand}
+         */
+        _computeExtraSuggestionViews() {
+            return insertAndReplace(this.extraSuggestions.map(suggestable => {
+                return {
+                    suggestable: replace(suggestable),
+                };
+            }));
         },
         /**
          * @private
@@ -960,7 +970,7 @@ registerModel({
          * @return {boolean}
          */
         _computeHasSuggestions() {
-            return this.mainSuggestionViews.length > 0 || this.extraSuggestionViews.length > 0;
+            return this.mainSuggestions.length > 0 || this.extraSuggestions.length > 0;
         },
         /**
          * @private
@@ -1024,11 +1034,21 @@ registerModel({
          * @private
          * @returns {Record[]}
          */
-        _computeMainSuggestionViews() {
+        _computeMainSuggestions() {
             if (this.suggestionDelimiterPosition === undefined) {
                 return clear();
             }
         },
+        /**
+         * @returns {FieldCommand}
+         */
+        _computeMainSuggestionViews() {
+            return insertAndReplace(this.mainSuggestions.map(suggestable => {
+                return {
+                    suggestable: replace(suggestable),
+                };
+            }));
+        },
         /**
          * @private
          * @returns {string}
@@ -1389,21 +1409,9 @@ registerModel({
             mainSuggestedRecords.length = Math.min(mainSuggestedRecords.length, limit);
             extraSuggestedRecords.length = Math.min(extraSuggestedRecords.length, limit - mainSuggestedRecords.length);
             this.update({
-                extraSuggestionViews: insertAndReplace(
-                    extraSuggestedRecords.map(record => {
-                        return {
-                            suggestable: replace(record.suggestable),
-                        };
-                    }),
-                ),
+                extraSuggestions: replace(extraSuggestedRecords.map(record => record.suggestable)),
                 hasToScrollToActiveSuggestionView: true,
-                mainSuggestionViews: insertAndReplace(
-                    mainSuggestedRecords.map(record => {
-                        return {
-                            suggestable: replace(record.suggestable),
-                        };
-                    }),
-                ),
+                mainSuggestions: replace(mainSuggestedRecords.map(record => record.suggestable)),
             });
         },
         /**
@@ -1490,6 +1498,9 @@ registerModel({
             inverse: 'composerViewOwnerAsEmoji',
             isCausal: true,
         }),
+        extraSuggestions: many('ComposerSuggestable', {
+            compute: '_computeExtraSuggestions',
+        }),
         /**
          * Determines the extra suggestions.
          */
@@ -1595,6 +1606,9 @@ registerModel({
         textareaLastInputValue: attr({
             default: "",
         }),
+        mainSuggestions: many('ComposerSuggestable', {
+            compute: '_computeMainSuggestions',
+        }),
         /**
          * Determines the main suggestions.
          */