Introduce a reusable providerLogo snippet to consolidate logo markup (normal
and large variants) and to render the instance badge for self-hosted GitLab.
Replace duplicated inline SVG spans with {@render providerLogo(...)} calls.
Also:
- update the Azure DevOps SVG path (comment notes simple-icons v11.15.0 as source)
- add providerColor cases for gitea and azure-devops and expose light-theme
CSS vars for their colors
- overhaul provider logo CSS (sizes, brand-icon class, instance badge, borders
and theme-aware vars) to unify appearance and spacing.