remove ui namespace which is not really used, move CameraData in camera_modes.h to avoid the inclusion of canva.h

src/image.h

@@ -1,7 +1,5 @@
 #pragma once
 
-namespace ui {
-
 class Image
 {
 public:
@@ -35,5 +33,3 @@ public:
     void create() { m_data = std::make_unique<uint8_t[]>(size()); }
     Image resize(int w, int h);
 };
-
-}