feat(highlight): migrate to tree-house with Helix queries

Replace tree-sitter-highlight dep with tree-house crate from Helix
editor. Add ropey dependency required by tree-house.

Reorganize query files from Helix's runtime/queries/ for all 14
supported languages:
- bash, c, css, go, html, javascript, json, markdown, nix, python,
  rust, toml, typescript, yaml
- Include ecma, _javascript, _typescript base dirs for JS/TS inheritance
- Copy highlights.scm, injections.scm, locals.scm where available

This commit establishes the foundation; highlight.rs implementation
will follow in subsequent commits.

queries/css/highlights.scm

@@ -0,0 +1,99 @@
+(comment) @comment
+
+[
+  (tag_name)
+  (nesting_selector)
+  (universal_selector)
+] @tag
+
+[
+  "~"
+  ">"
+  "+"
+  "-"
+  "*"
+  "/"
+  "="
+  "^="
+  "|="
+  "~="
+  "$="
+  "*="
+] @operator
+
+[
+  "and"
+  "not"
+  "only"
+  "or"
+] @keyword.operator
+
+(attribute_selector (plain_value) @string)
+
+(property_name) @variable.other.member
+(plain_value) @constant
+
+((property_name) @variable
+  (#match? @variable "^--"))
+((plain_value) @variable
+  (#match? @variable "^--"))
+
+(class_name) @label
+(feature_name) @variable.other.member
+(function_name) @function
+(id_name) @label
+(namespace_name) @namespace
+
+(attribute_name) @attribute
+(pseudo_element_selector (tag_name) @attribute)
+(pseudo_class_selector (class_name) @attribute)
+
+[
+  "@charset"
+  "@import"
+  "@keyframes"
+  "@media"
+  "@namespace"
+  "@supports"
+  (at_keyword)
+  (from)
+  (important)
+  (to)
+  (keyword_query)
+  (keyframes_name)
+  (unit)
+] @keyword
+
+; @apply something;
+(at_rule
+  . (at_keyword) @keyword
+  . (keyword_query) @constant
+  (#eq? @keyword "@apply"))
+
+[
+  "#"
+  "."
+] @punctuation
+
+(string_value) @string
+(color_value "#" @string.special)
+(color_value) @string.special
+
+(integer_value) @constant.numeric.integer
+(float_value) @constant.numeric.float
+
+[
+  ")"
+  "("
+  "["
+  "]"
+  "{"
+  "}"
+] @punctuation.bracket
+
+[
+  ","
+  ";"
+  ":"
+  "::"
+] @punctuation.delimiter