Show participant team review state and gating

Expand submission workflow instructions

Add challenge communication channels

Add challenge participation guidance

Expand challenge description and evaluation details

Lock participant profiles and remember email

Add shared navigation and challenge terms page

Refine submission workflow usability

Split participation workflow from challenge landing page

Add app-scoped OAuth submission workflow

Collect team profile and terms consent

Add OAuth-backed challenge submission frontend

Add submission and leaderboard frontend

Add mobile responsive breakpoint for nav, hero, and spacing

Rename to AV Causal Scenario Retrieval Challenge; move hero text below banner; externalize CSS

Build challenge landing page with styled layout and banner

initial commit