shader: Initial support for textures and TEX

src/shader_recompiler/file_environment.h

@@ -3,7 +3,7 @@
 #include <vector>
 
 #include "common/common_types.h"
-#include "environment.h"
+#include "shader_recompiler/environment.h"
 
 namespace Shader {
 
@@ -14,6 +14,8 @@ public:
 
     u64 ReadInstruction(u32 offset) override;
 
+    u32 TextureBoundBuffer() override;
+
     std::array<u32, 3> WorkgroupSize() override;
 
 private: