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/devices/koreader/scenarios/Sync Annotations (Per-Book SHA-256).yml

@@ -0,0 +1,44 @@
+info:
+  name: KOReader Sync Annotations - Per-Book SHA-256
+  type: http
+  seq: 4
+http:
+  method: POST
+  url: '{{base_url}}/api/v1/koreader/sync/bookmarks'
+  auth: inherit
+  body:
+    type: json
+    jsonBody: "{\n    \"book_uuid\": \"{{book_uuid"
+  headers:
+  - key: Authorization
+    value: Bearer {{koreader_device_token
+
+docs: |-
+  ## KOReader Sync Annotations - Per-Book SHA-256
+  
+    Synchronizes annotations (highlights) from KOReader with per-annotation SHA-256 hashes for multi-book sync.
+  
+    **Method:** POST
+  
+    **Endpoint:** /api/v1/koreader/sync/bookmarks
+  
+    **Authentication:** Bearer token (KOReader device token)
+  
+    **Request Body:**
+    - `book_uuid` (string): Primary book UUID
+    - `highlights` (array): Array of highlight objects
+      - `text` (string): Highlighted text
+      - `pos0`, `pos1` (string): EPUB CFI positions
+      - `color` (string): Highlight color (hex)
+      - `page` (number): Page number
+      - `book_sha256` (string): SHA-256 hash for this specific book
+  
+    **Response:**
+    - `highlights_synced` (number): Number of highlights synced
+  
+    **Status Codes:**
+    - 200: Success
+    - 401: Unauthorized
+    - 500: Internal server error
+  
+    **Note:** Each highlight can include its own book_sha256, allowing annotations from multiple books in a single request.