feat: Enhance surface setup chooser with compact mode and cancel functionality

scripts/editors/stage/stage_asset_browser.gd

@@ -47,7 +47,8 @@ func build_ui(ui_layer: CanvasLayer, ui_font: Font, emoji_font: Font, sandbox_th
 	selector_dim = ColorRect.new()
 	selector_dim.name = "SelectorDim"
 	selector_dim.color = Color(0.0, 0.0, 0.0, SELECTOR_DIM_ALPHA)
-	selector_dim.mouse_filter = Control.MOUSE_FILTER_IGNORE
+	# Keep clicks outside the modal from reaching the Stage canvas beneath it.
+	selector_dim.mouse_filter = Control.MOUSE_FILTER_STOP
 	selector_dim.set_anchors_and_offsets_preset(Control.PRESET_FULL_RECT)
 	selector_dim.visible = false
 	ui_layer.add_child(selector_dim)
@@ -55,7 +56,7 @@ func build_ui(ui_layer: CanvasLayer, ui_font: Font, emoji_font: Font, sandbox_th
 	selector = ASSET_SELECTOR_SCENE.instantiate() as AssetSelector
 	selector.item_selected.connect(func(entry: Dictionary) -> void: asset_selected_requested.emit(entry))
 	selector.cancelled.connect(_on_selector_cancelled)
-	selector.popup_hide.connect(_on_selector_cancelled)
+	selector.popup_hide.connect(_on_selector_popup_hide)
 	selector.browse_requested.connect(show_browse_dialog)
 	selector.refresh_requested.connect(func() -> void: refresh_requested.emit())
 	selector.make_artwork_requested.connect(func() -> void: make_artwork_requested.emit())
@@ -281,6 +282,19 @@ func _on_selector_cancelled() -> void:
 		selector_cancel_requested.emit()
 
 
+func _on_selector_popup_hide() -> void:
+	if not selector_open:
+		return
+	# PopupPanel can hide itself when it loses focus. Keep the chooser alive so an
+	# outside click cannot silently cancel the user's scenery setup.
+	call_deferred("_restore_selector_after_unexpected_hide")
+
+
+func _restore_selector_after_unexpected_hide() -> void:
+	if selector_open and selector != null and not selector.visible:
+		selector.popup_centered()
+
+
 func get_selector() -> AssetSelector:
 	return selector