Light mode overhaul, table updates, & elevation floating removal

[Shrinks99]

Changes

• Removes elevation="floating" and replaces all instances of it within the library with elevation="overlay"
  • I will update Explorer and GovStudio, frankly I'm pretty sure this is used nowhere else and it really just made things more complicated for no reason. Simplify!
• Adjusts light mode colour tokens, now starts white and gets darker as elevation increases — inverse of dark mode (and how it should be, I picked the wrong tokens before 🥲 )
• Update SortButton styling
• Update Table styling
  • Fix table hover colour on light mode

Docs

• Updates Table docs page
• Adds SortButton docs content

Screenshots

Before

After

[tmccoy14]

Good stuff!