Update swagger for json login, api prefix, direct upload, markdown read

public/swagger/v1/users/login.yaml

@@ -6,13 +6,10 @@ paths:
     - users
     requestBody:
       content:
+        application/json:
+          $ref: "#/components/schemas/requestLogin"
         application/x-www-form-urlencoded:
-          schema:
-            type: object
-            properties:
-              DnDex-User:
-                type: string
-                example: "namespace"
+          $ref: "#/components/schemas/requestLogin"
     responses:
       200:
         content:
@@ -26,3 +23,13 @@ paths:
                 salt:
                   type: string
                   example: def-456
+
+components:
+  schemas:
+    requestLogin:
+      schema:
+        type: object
+        properties:
+          DnDex-User:
+            type: string
+            example: "namespace"