Add documentation for "is-ready" endpoint to check stored object status

- Introduced `/1.0/doc-store/stored-object/{uuid}/is-ready` endpoint to retrieve the status of a stored object.
- Added path parameter for `uuid` and returned `status` property with `empty`, `ready`, `pending`, or `failure` states.

src/Bundle/ChillDocStoreBundle/chill.api.specs.yaml

@@ -54,6 +54,38 @@ paths:
                 422:
                     description: "Invalid data"
 
+    /1.0/doc-store/stored-object/{uuid}/is-ready:
+        get:
+            tags:
+                - storedobject
+            summary: Get the status of a stored object
+            parameters:
+                -   in: path
+                    name: uuid
+                    required: true
+                    allowEmptyValue: false
+                    description: The UUID of the storedObject
+                    schema:
+                        type: string
+                        format: uuid
+            responses:
+                200:
+                    description: "OK"
+                    content:
+                        application/json:
+                            schema:
+                                type: object
+                                properties:
+                                    id:
+                                        type: integer
+                                    filename:
+                                        type: string
+                                    status:
+                                        type: string
+                                        enum: [empty, ready, pending, failure]
+                                    type:
+                                        type: string
+
     /1.0/doc-store/async-upload/temp_url/{uuid}/generate/post:
         get:
             tags: