feat: add outline for block that is looked

src/shaders/outline_f_shader.glsl

@@ -0,0 +1,7 @@
+#version 460
+
+out vec4 frag_color;
+
+void main(void) {
+    frag_color = vec4(0.0, 0.0, 0.0, 1.0);
+}

src/shaders/outline_v_shader.glsl

@@ -0,0 +1,10 @@
+#version 460
+
+layout (location = 0) in vec3 vertices_pos;
+
+uniform mat4 mv_matrix;
+uniform mat4 proj_matrix;
+
+void main(void) {
+    gl_Position = proj_matrix * mv_matrix * vec4(vertices_pos, 1.0);
+}