Route icon results through UI events (T-607)

app-modern/ui/gio/shell.go

@@ -66,6 +66,10 @@ type AppShell struct {
 	categoryControls map[string]*widget.Clickable
 	rows             map[string]*rowControls
 	icons            map[string]paint.ImageOp
+	iconReferences   map[string]string
+	iconRequests     map[string]application.IconEventIdentity
+	iconApplied      map[string]application.IconEventIdentity
+	iconFailures     map[string]application.IconFailureCode
 	lastRendered     int
 	detailRendered   bool
 }
@@ -83,14 +87,21 @@ func NewAppShell(
 		categoryControls: make(map[string]*widget.Clickable),
 		rows:             make(map[string]*rowControls),
 		icons:            make(map[string]paint.ImageOp),
+		iconReferences:   make(map[string]string),
+		iconRequests:     make(map[string]application.IconEventIdentity),
+		iconApplied:      make(map[string]application.IconEventIdentity),
+		iconFailures:     make(map[string]application.IconFailureCode),
 	}
 	shell.search.SingleLine = true
 	shell.SetItems(items)
 	return shell
 }
 
-// ApplyIcon stores a background-decoded image for future Layout calls.
+// ApplyIcon stores a decoded image for future Layout calls.
+// It is UI-goroutine-only; background workers must publish application events.
 func (shell *AppShell) ApplyIcon(appID string, icon image.Image) {
+	delete(shell.iconApplied, appID)
+	delete(shell.iconFailures, appID)
 	if icon == nil {
 		delete(shell.icons, appID)
 		return
@@ -104,18 +115,39 @@ func (shell *AppShell) SetItems(items []application.CatalogListItem) {
 
 	nextRows := make(map[string]*rowControls, len(items))
 	nextIcons := make(map[string]paint.ImageOp, len(items))
+	nextReferences := make(map[string]string, len(items))
+	nextRequests := make(map[string]application.IconEventIdentity, len(items))
+	nextApplied := make(map[string]application.IconEventIdentity, len(items))
+	nextFailures := make(map[string]application.IconFailureCode, len(items))
 	for _, item := range items {
 		controls := shell.rows[item.ID]
 		if controls == nil {
 			controls = new(rowControls)
 		}
 		nextRows[item.ID] = controls
-		if icon, exists := shell.icons[item.ID]; exists {
-			nextIcons[item.ID] = icon
+		reference := canonicalIconReference(item.IconRef)
+		nextReferences[item.ID] = reference
+		if previous, exists := shell.iconReferences[item.ID]; exists && previous == reference {
+			if icon, exists := shell.icons[item.ID]; exists {
+				nextIcons[item.ID] = icon
+			}
+			if request, exists := shell.iconRequests[item.ID]; exists && request.Reference == reference {
+				nextRequests[item.ID] = request
+			}
+			if applied, exists := shell.iconApplied[item.ID]; exists && applied.Reference == reference {
+				nextApplied[item.ID] = applied
+			}
+			if failure, exists := shell.iconFailures[item.ID]; exists {
+				nextFailures[item.ID] = failure
+			}
 		}
 	}
 	shell.rows = nextRows
 	shell.icons = nextIcons
+	shell.iconReferences = nextReferences
+	shell.iconRequests = nextRequests
+	shell.iconApplied = nextApplied
+	shell.iconFailures = nextFailures
 
 	nextCategories := make(map[string]*widget.Clickable)
 	for _, category := range append([]string{""}, shell.model.Categories()...) {