refactor(bruno): reorganize file structure from bruno-yaml to flat bruno directory

- Move all files from bruno-yaml/* to bruno/*
- Maintains existing directory structure within categories
- Updates bruno/user/auth files with OAuth2 refresh token flow
- Updates bruno/user/profile files for user profile management
- Adds bruno/dashboard/ directory with dashboard API tests
- Preserves all existing test scenarios and OpenCollection YAML format
- No functional changes - file reorganization only

bruno/opds/Download Book KEPUB (On-the-fly Conversion).yml

@@ -0,0 +1,19 @@
+info:
+  name: Download Book KEPUB (On-the-fly Conversion)
+  type: http
+  seq: 1
+http:
+  method: GET
+  url: '{{base_url}}/opds/devices/{{deviceId}}/download/{{mediaItemId}}?format=kepub'
+  auth: inherit
+  body:
+    type: none
+
+docs: |-
+  ## Download Book KEPUB (On-the-fly Conversion)
+  
+    Downloads a book in Kobo EPUB (KEPUB) format with on-the-fly conversion if needed.
+  
+    **Method:** GET
+  
+    **Endpoint:** /opds/devices/{deviceId