refactor: Upgrade Ant version

[ShrimpCryptid]

Upgrades the Ant Design component library to 5.16.2 from 3.26.20 and fixes (most of) the elements that broke as a result.

Estimated review size: M/L, 30-40 minutes.

• Updates Ant Design to 5.16.2.
• Changes StyleProvider to use a unified theme variable that is passed down through CSS variables and the Ant ConfigProvider.
• Removes less files and plugins.
• Fixes various CSS/design problems that arose as part of the change. (see list below)
• Updates Ant components that had changed APIs.

Video talk-through (🔊):

https://github.com/allen-cell-animated/website-3d-cell-viewer/assets/30200665/b06c35cf-0b7b-437d-a7e0-c6eca979dbc0

Questions/Discussion:

• Are there better ways we can be handling CSS variables and styling?
• See note here about modifying our styling to align with Ant: #81

Thanks for contributing!

[ShrimpCryptid]

TODO list:

• [x] Fix vertical alignment of channel settings rows
• [x] Fix icon alignment in icon buttons
• [x] Fix background colors
• [x] Fix background card border radii
• [x] Fix element alignment in the control toolbar
• [x] Fix underlines on links so they only appear when focused
• [x] Fix card spacing on sections headers
• [x] Fix underline color on title
• [x] Button hover and selection colors
• [x] Fix H2 text colors (should be white)
• [x] Fix font size on main page
• [x] Fix disabled buttons having hover color
• [x] Fix In-review flag color
• [x] Fix palette dropdown button colors when clicking
• [x] Fix view mode dropdown color
• [x] Fix tooltip color
• [x] Fix clipping menu
• [x] Add StyleProvider to base viewer
• [x] Remove unused style variables
• [x] Replace Dropdown overlay w/ menu
• [x] Fix bug where moving one of the clipping range sliders causes the others to also move -> opened as new issue #222

[ShrimpCryptid]

Writing Cameron's feedback as a TODO list:

• [x] I'm getting scroll bars on the bottom and right of the clipping panel Could not repro
• [x] Toggle-able buttons on the toolbar no longer enter their "active" state (I believe they should get a background when e.g. the axes are toggled on)
• [x] There's some weird margin around items in the metadata viewer
• [x] Ant's dropdowns are different now. Might be worth checking in with UX on whether we should do anything about it? Will address in #220
• [x] Should the text in the render mode dropdown button be a bit easier to see when the dropdown is open?
• [x] Might not be worth fixing with a rework coming soon, but isosurface settings sliders are also tough to see now.
• [x] The side panel is a very slightly different color than the header bar (this is the UI being out of compliance previously, not an issue this update created!) I believe this is correct styling actually