[IMP] website: improve events on we-matrix

This commit improves the handling of events on the editor's we-matrix.
The fields that make up the list trigger a preview at each input and the
user can navigate through the matrix with the keyboard.

task-2601533

Part-of: odoo/odoo#81241

addons/website/static/src/snippets/s_chart/options.js

@@ -17,7 +17,7 @@ options.registry.InnerChart = options.Class.extend({
         'click we-button.add_row': '_onAddRowClick',
         'click we-button.o_we_matrix_remove_col': '_onRemoveColumnClick',
         'click we-button.o_we_matrix_remove_row': '_onRemoveRowClick',
-        'blur we-matrix input': '_onMatrixInputFocusOut',
+        'input we-matrix input': '_onMatrixInputInput',
         'focus we-matrix input': '_onMatrixInputFocus',
     }),
 
@@ -476,9 +476,8 @@ options.registry.InnerChart = options.Class.extend({
     },
     /**
      * @private
-     * @param {Event} ev
      */
-    _onMatrixInputFocusOut: function (ev) {
+    _onMatrixInputInput() {
         this._reloadGraph();
     },
     /**