refactor: restructure Bruno API collection for consistency

Standardize all Bruno API request files with consistent formatting and
structure to improve maintainability and readability.

Changes include:
- Consolidate URL parameters into main URL instead of separate definitions
- Standardize quote style (double quotes throughout)
- Add proper settings section with defaults (timeout, redirects, etc.)
- Improve YAML formatting with literal style for multi-line content
- Remove redundant fields (disabled: false)
- Clean up header and body structure
- Update sequence numbers for better organization
- Add scenarios folder structure for organized test groupings

Removes obsolete Search Invalid Library ID test case.

Environment configuration updated with new library_id for testing.

These changes improve the Bruno collection's maintainability and make
it easier to create new API requests following established patterns.

bruno/media-items/scenarios/folder.yml

@@ -0,0 +1,6 @@
+info:
+  name: scenarios
+  type: folder
+  seq: 20
+
+request: {}