Finished video grid main elements

[logbasem]

• Implemented video grid with 5 cameras
• User clicks on dropdown to select camera path, then clicks "Add Camera" to add the associated feed to the first available (non-populated) container.
• Placeholder text for no camera
• Loading indicator for when video is still loading after add
• Start of camera bar at top of screen
• Works with fake backend, has not been tested with real feeds

Figma Design

UI Screenshot

[onkoe]

lgtm! please feel free to solve these kinda-minor nits if you have time.