docs: add OpenAPI documentation

openapi/schemas/Recipe.yaml

@@ -0,0 +1,39 @@
+type: "object"
+properties:
+  id:
+    $ref: "./Id.yaml"
+    readOnly: true
+    description: "Unique identifier of the recipe"
+  name:
+    $ref: "./NonBlankString.yaml"
+    description: "Name"
+  description:
+    $ref: "./NonBlankString.yaml"
+    description: "Description"
+  changedAt:
+    $ref: "./DateTime.yaml"
+    readOnly: true
+    description: "Last point in time when the recipe was changed"
+  categories:
+    type: "array"
+    items:
+      $ref: "./NonBlankString.yaml"
+    description: "Category names"
+  ingredients:
+    type: "array"
+    minItems: 1
+    items:
+      $ref: "./NonBlankString.yaml"
+    description: "Step descriptions"
+  steps:
+    type: "array"
+    minItems: 1
+    items:
+      $ref: "./NonBlankString.yaml"
+    description: "Ingredient names"
+required:
+  - name
+  - description
+  - categories
+  - ingredients
+  - steps