BREAKING!: rewrite config api and update styles

- move config to lua
- use rose for search match
- fix background flicker when automatically switching to dawn
- remove unneeded highlights (please report regressions)
  - remove deprecated `LspDiagnostics*`
  - remove `LspReference*`
- improve overall consistency between elements
  - non-treesitter updates to match treesitter styles
  - update popup menu scrollbar and selection
  - update telescope selection
  - match cursorcolumn to cursorline

lua/rose-pine/palette.lua

@@ -1,4 +1,6 @@
-local variants = {
+local palette = {}
+
+palette = {
 	main = {
 		base = '#191724',
 		surface = '#1f1d2e',
@@ -55,14 +57,6 @@ local variants = {
 	},
 }
 
-local palette = variants.main
-
-if string.match(vim.g.rose_pine_variant or '', 'moon') then
-	palette = variants.moon
-elseif string.match(vim.g.rose_pine_variant or '', 'dawn') then
-	palette = variants.dawn
-end
-
 vim.tbl_deep_extend('force', palette, { none = 'NONE' })
 
 return palette