Fix RCSS syntax errors and hide floating windows by default

Fixed unsupported RCSS properties in editor.rcss:
- Removed 'outline: none;' (line 233) - not supported in RmlUi
- Changed 'display: grid;' to 'display: flex; flex-wrap: wrap;' (line 295)
- Removed 'grid-template-columns' (line 296) - not needed with flex
- Removed 'object-fit: cover;' (line 322) - not supported in RmlUi

Hidden floating windows by default:
- Command window (undo/redo/clear buttons)
- Status window
- Control buttons
- Top left menu

These were showing on startup causing 3 buttons to appear at the top.
They should be shown/hidden as needed by the application logic.

Author: claude

scen_edit/view/rcss/editor.rcss

@@ -230,7 +230,6 @@
 
 .form-input-number:focus {
     border-color: #3a7ebf;
-    outline: none;
 }
 
 /* Map Editor specific */
@@ -292,8 +291,8 @@
 }
 
 .texture-grid {
-    display: grid;
-    grid-template-columns: repeat(auto-fill, minmax(64dp, 1fr));
+    display: flex;
+    flex-wrap: wrap;
     gap: 5dp;
     margin-bottom: 10dp;
 }
@@ -319,7 +318,6 @@
 .texture-item img {
     width: 100%;
     height: 100%;
-    object-fit: cover;
 }
 
 .texture-settings {

scen_edit/view/view.lua

@@ -83,22 +83,22 @@ function View:InitializeRmlUi()
         return
     end
 
-    -- Initialize floating windows
+    -- Initialize floating windows (hidden by default)
     self.commandWindow = RmlUiCommandWindow()
     self.commandWindow:Initialize()
-    self.commandWindow:Show()
+    -- self.commandWindow:Show()  -- Hidden by default
 
     self.statusWindow = RmlUiStatusWindow()
     self.statusWindow:Initialize()
-    self.statusWindow:Show()
+    -- self.statusWindow:Show()  -- Hidden by default
 
     self.controlButtons = RmlUiControlButtons()
     self.controlButtons:Initialize()
-    self.controlButtons:Show()
+    -- self.controlButtons:Show()  -- Hidden by default
 
     self.topLeftMenu = RmlUiTopLeftMenu()
     self.topLeftMenu:Initialize()
-    self.topLeftMenu:Show()
+    -- self.topLeftMenu:Show()  -- Hidden by default
 
     -- Initialize editors (create instances but don't show)
     self.triggerEditor = RmlUiTriggerEditor()