[MM-44123] Advanced Text Editor Feature Flag (#20184)

* Advance Text Editor Feature Flag

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

model/feature_flags.go

@@ -71,6 +71,8 @@ type FeatureFlags struct {
 	CloudFree bool
 
 	CommandPalette bool
+
+	AdvancedTextEditor bool
 }
 
 func (f *FeatureFlags) SetDefaults() {
@@ -96,6 +98,7 @@ func (f *FeatureFlags) SetDefaults() {
 	f.InsightsEnabled = false
 	f.CloudFree = false
 	f.CommandPalette = false
+	f.AdvancedTextEditor = false
 }
 
 func (f *FeatureFlags) Plugins() map[string]string {