Super sidebar avatar read brand/home link to screen-readers

What does this MR do and why?

"Home" link in super sidebar has no accessible name (recordings) as is read as "Link {url}" in screen-readers. This could be improved by including the relevant brand name as the accessible name or alternatively use generic "home" terminology to provide a meaningful label.

Update to add "Homepage" title/tooltip as per #392963 (closed) and !114523 (merged)

Changes

• Add Dashboard title attribute to logo link in super sidebar
• Add tooltip to logo

Header	Super sidebar

Screenshots or screen recordings

OS	Browser	Screen-reader	Before	After
Windows	Chrome	JAWS	dashboard-link-jaws-before	dashboard-link-jaws-after
Windows	Firefox	NVDA	dashboard-link-nvda-before	dashboard-link-nvda-after
MacOS	Safari	VoiceOver	dashboard-link-voiceover-before	dashboard-link-voiceover-after

How to set up and validate locally

• Enable the feature flag in rails console with rails c

Feature.enable(:super_sidebar_nav)

• Enable the "New navigation" setting toggle from the user dropdown

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #394970 (closed)