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/hack/highlights.scm

@@ -43,7 +43,7 @@
  "include_once"
  "require"
  "require_once"
-] @include
+] @keyword.import
 
 [
   "new"
@@ -184,10 +184,10 @@
 ] @operator
 
 (integer) @number
-(float) @float
+(float) @number.float
 
 (parameter
-  (variable) @parameter)
+  (variable) @variable.parameter)
 
 (call_expression
   function: (qualified_identifier (identifier) @function.call .))
@@ -197,23 +197,23 @@
 
 (call_expression
   function: (selection_expression
-              (qualified_identifier (identifier) @method.call .)))
+              (qualified_identifier (identifier) @function.method.call .)))
 
 (qualified_identifier
-  (_) @namespace .
+  (_) @module .
   (_))
 
 (use_statement
   (qualified_identifier
-  (_) @namespace .)
+  (_) @module .)
   (use_clause))
 
 (use_statement
   (use_type "namespace")
   (use_clause
     (qualified_identifier
-         (identifier) @namespace .)
-    alias: (identifier)? @namespace))
+         (identifier) @module .)
+    alias: (identifier)? @module))
 
 (use_statement
   (use_type "const")
@@ -239,8 +239,8 @@
 (use_clause
   (use_type "namespace")
   (qualified_identifier
-  (_) @namespace .)
-  alias: (identifier)? @namespace)
+  (_) @module .)
+  alias: (identifier)? @module)
 
 (use_clause
   (use_type "function")
@@ -263,7 +263,7 @@
 (function_declaration
   name: (identifier) @function)
 (method_declaration
-  name: (identifier) @method)
+  name: (identifier) @function.method)
 
 (type_arguments
   [ "<" ">" ] @punctuation.bracket)
@@ -279,7 +279,7 @@
   "\\" @punctuation.delimiter)
 
 (ternary_expression
-  ["?" ":"] @conditional.ternary)
+  ["?" ":"] @keyword.conditional.ternary)
 
 [
   "if"
@@ -287,13 +287,13 @@
   "elseif"
   "switch"
   "case"
-] @conditional
+] @keyword.conditional
 
 [
   "try"
   "catch"
   "finally"
-] @exception
+] @keyword.exception
 
 [
   "for"
@@ -302,7 +302,7 @@
   "do"
   "continue"
   "break"
-] @repeat
+] @keyword.repeat
 
 [
  (string)