Correct accessibility issues with schemas

• focus is lost when opening or closing the schema in schemas section

• OpenAPI 2.0/3.0: the information about the property being expanded is narrated only after navigating into […]/information group

https://github.com/user-attachments/assets/19213d46-80e3-4892-ba70-fecad2090bef

• OpenAPI 3.1: keyboard navigation gets trapped in expanded properties, jumps between the property name and collapse all button

https://github.com/user-attachments/assets/242dde3a-143d-4480-96f3-d48e7287e3d5

• OpenAPI 3.1: focus is not visible for schema name and properties with tab navigation

• OpenAPI 3.1: no name/label for article section

• OpenAPI 2.0/3.0 schema buttons - provide indication which property the button expands/collapses

• OpenAPI 3.1 schema buttons - provide description for expanded/collapsed state

• required property indicated by * - provide label/description required for screen reader users instead of *

This task covers issues originally reported in:

• https://github.com/swagger-api/swagger-ui/issues/5248
• https://github.com/swagger-api/swagger-ui/issues/7350

Start at the schemas section and reproduce the listed keyboard, focus, labeling, and screen-reader issues for OpenAPI 2.0, 3.0, and 3.1. Work through each checklist item and verify that focus remains usable, controls expose their property and expanded state, required fields are labeled, and the article has a name.