feat!: align standard captures with upstream

Problem: Sharing highlight queries with upstream tree-sitter and
Helix is difficult.

Solution: Where reasonable, use capture names in tree-sitter's standard
list or Helix's Atom-style hierarchy.

Specifically:

* tree-sitter "standard capture names"
  (3f44b89685/highlight/src/lib.rs (L20-L72)):

  - `@parameter` -> `@variable.parameter`
  - `@field` -> `@variable.member`
  - `@namespace` -> `@module`
  - `@float` -> `@number.float`
  - `@symbol` -> `@string.special.symbol`
  - `@string.regex` -> `@string.regexp`
  - `@text.*` -> `@markup.*` (`strong`, `italic`, `link`, `strikethrough`; with exceptions; see below)
  - `@text.title` -> `@markup.heading`
  - `@text.literal` -> `@markup.raw`
  - `@text.reference` -> `@markup.link`
  - `@text.uri` -> `@markup.link.url` (in markup links)
  - `@string.special` -> `@markup.link.label` (non-url links)
  - `@punctuation.special` -> `@markup.list` (markdown lists only; move subitems from `@text.todo`)

* Helix captures
  (https://docs.helix-editor.com/master/themes.html#syntax-highlighting):

  - `@method` -> `@function.method`
  - `@method.call` -> `@function.method.call`
  - `@text.{todo,warning,note,danger}` -> `@comment.{error,warning,hint,info,todo}`
  - `@text.diff.{add,delete,}` -> `@diff.{plus,minus,delta}`
  - `@text.uri` -> `@string.special.url` (outside markup)
  - `@preproc` -> `@keyword.directive`
  - `@define` -> `@keyword.directive`(`.define`?)
  - `@storageclass` -> `@keyword.storage`
  - `@conditional` -> `@keyword.conditional`
  - `@debug` -> `@keyword.debug`
  - `@exception` -> `@keyword.exception`
  - `@include` -> `@keyword.import`
  - `@repeat` -> `@keyword.repeat`

* cleanup

  - remove some redundant `@conceal` (but still allow it for conceal-only patterns)
  - remove obsolete `@error` (syntax linting is out of scope for this repo)
  - sort, cleanup capture list in `CONTRIBUTING.md`

queries/cairo/highlights.scm

@@ -3,17 +3,17 @@
 [
   "%builtins"
   "%lang"
-] @preproc
+] @keyword.directive
 
 ; Includes
 
-(import_statement [ "from" "import" ] @include module_name: (dotted_name (identifier) @namespace . ))
+(import_statement [ "from" "import" ] @keyword.import module_name: (dotted_name (identifier) @module . ))
 
 [
   "as"
   "use"
   "mod"
-] @include
+] @keyword.import
 
 ; Variables
 
@@ -21,24 +21,24 @@
 
 ; Namespaces
 
-(namespace_definition (identifier) @namespace)
+(namespace_definition (identifier) @module)
 
 (mod_item
-  name: (identifier) @namespace)
+  name: (identifier) @module)
 
-(use_list (self) @namespace)
+(use_list (self) @module)
 
-(scoped_use_list (self) @namespace)
+(scoped_use_list (self) @module)
 
 (scoped_identifier
-  path: (identifier) @namespace)
+  path: (identifier) @module)
 
 (scoped_identifier
  (scoped_identifier
-  name: (identifier) @namespace))
+  name: (identifier) @module))
 
 (scoped_type_identifier
-  path: (identifier) @namespace)
+  path: (identifier) @module)
 
 ((scoped_identifier
   path: (identifier) @type)
@@ -65,13 +65,13 @@
   (#lua-match? @constant "^[A-Z]"))
 
 (scoped_use_list
-  path: (identifier) @namespace)
+  path: (identifier) @module)
 
 (scoped_use_list
   path: (scoped_identifier
-          (identifier) @namespace))
+          (identifier) @module))
 
-(use_list (scoped_identifier (identifier) @namespace . (_)))
+(use_list (scoped_identifier (identifier) @module . (_)))
 
 (use_list (identifier) @type (#lua-match? @type "^[A-Z]"))
 
@@ -125,47 +125,47 @@
 [
   "tempvar"
   "extern"
-] @storageclass
+] @keyword.storage
 
 [
   "if"
   "else"
   "match"
-] @conditional
+] @keyword.conditional
 
 [
   "loop"
-] @repeat
+] @keyword.repeat
 
 [
   "assert"
   "static_assert"
   "nopanic"
-] @exception
+] @keyword.exception
 
 ; Fields
 
-(implicit_arguments (typed_identifier (identifier) @field))
+(implicit_arguments (typed_identifier (identifier) @variable.member))
 
-(member_expression "." (identifier) @field)
+(member_expression "." (identifier) @variable.member)
 
-(call_expression (assignment_expression left: (identifier) @field))
+(call_expression (assignment_expression left: (identifier) @variable.member))
 
-(tuple_expression (assignment_expression left: (identifier) @field))
+(tuple_expression (assignment_expression left: (identifier) @variable.member))
 
-(field_identifier) @field
+(field_identifier) @variable.member
 
-(shorthand_field_initializer (identifier) @field)
+(shorthand_field_initializer (identifier) @variable.member)
 
 ; Parameters
 
-(arguments (typed_identifier (identifier) @parameter))
+(arguments (typed_identifier (identifier) @variable.parameter))
 
-(call_expression (tuple_expression (assignment_expression left: (identifier) @parameter)))
+(call_expression (tuple_expression (assignment_expression left: (identifier) @variable.parameter)))
 
-(return_type (tuple_type (named_type . (identifier) @parameter)))
+(return_type (tuple_type (named_type . (identifier) @variable.parameter)))
 
-(parameter (identifier) @parameter)
+(parameter (identifier) @variable.parameter)
 
 ; Builtins
 
@@ -202,7 +202,7 @@
 
 ; Types
 
-(struct_definition . (identifier) @type (typed_identifier (identifier) @field)?)
+(struct_definition . (identifier) @type (typed_identifier (identifier) @variable.member)?)
 
 (named_type (identifier) @type .)