feat: add colors

breath exercise/breathing colors/get breathing colors.bru

@@ -0,0 +1,21 @@
+meta {
+  name: get breathing colors
+  type: http
+  seq: 1
+}
+
+get {
+  url: {{baseUrl}}/breathing-colors
+  body: none
+  auth: inherit
+}
+
+settings {
+  encodeUrl: true
+}
+
+docs {
+  Palette the app shows when creating a breathing template. Each item has
+  a `colors` array (one hex = solid, several = gradient). The user picks one
+  and sends its colors as `colors` on /breathing-templates.
+}