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

src/shader.h

@@ -1,8 +1,6 @@
 #pragma once
 #include "util.h"
 
-namespace ui {
-
 enum class kShaderUniform : uint16_t
 {
     MVP = const_hash("mvp"),
@@ -88,5 +86,3 @@ public:
     static void u_float(kShaderUniform id, float f);
     static void invalidate();
 };
-
-}