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`

tests/query/highlights/t32/keywords.cmm

@@ -3,15 +3,15 @@ PRIVATE &password
 ;        ^ @variable.builtin
 ENTRY &password
 ; <- @keyword
-;        ^ @parameter
+;        ^ @variable.parameter
 
 ENTRY %LINE &salt
 ; <- @keyword
 ;      ^ @constant.builtin
-;            ^ @parameter
+;            ^ @variable.parameter
 
 IF "&password"==""
-; <- @conditional
+; <- @keyword.conditional
 ;  ^ @string
 ;    ^ @variable.builtin
 ;             ^ @operator
@@ -21,7 +21,7 @@ IF "&password"==""
 ;   ^ @keyword.return
 )
 ELSE
-; <- @conditional
+; <- @keyword.conditional
 (
     PRIVATE &pass
 
@@ -33,9 +33,9 @@ ELSE
         GOSUB verify_password "&password"
 ;             ^ @function.call
         RETURNVALUES &pass
-;                     ^ @parameter
+;                     ^ @variable.parameter
         WAIT 10.ms
-;            ^ @float
+;            ^ @number.float
     )
 
     IF !&pass
@@ -63,7 +63,7 @@ FramePOS ,,,,Maximized
 ;        ^ @punctuation.delimiter
 ;            ^ @constant.builtin
 WinPOS 0% 50% 100% 35%
-;      ^ @float
+;      ^ @number.float
 COVerage.ListFunc
 
 ENDDO
@@ -80,11 +80,11 @@ verify_password:
 ; <- @function
 (
     PARAMETERS &password
-;               ^ @parameter
+;               ^ @variable.parameter
 
     SYStem.Option.KEYCODE "&password"
     SYStem.JtagClock  1kHz
-;                     ^ @float
+;                     ^ @number.float
     SYStem.Mode.Attach
 
     Data.Set N: EAXI:0x34000000 %Long 0x34000100 0x34000021 /verify
@@ -107,7 +107,7 @@ SUBROUTINE start_debug
     COVerage.ListModule %MULTI.OBC \sieve
 ;    ^ @keyword
 ;                        ^ @constant.builtin
-;                                  ^ @symbol
+;                                  ^ @string.special.symbol
 
     Var.DRAW flags[0..16] /Alternate 3
 ;    ^ @keyword

tests/query/highlights/t32/literals.cmm

@@ -8,19 +8,19 @@ sYmbol.NEW _InitialSP   0x34000100
 ;                       ^ @number
 
 DO ~~~~/test.cmm
-;  ^ @string.special
+;  ^ @string.special.path
 
 WAIT 1.ns
-;    ^ @float
+;    ^ @number.float
 
 SYStem.JtagClock  100.GHZ
-;                 ^ @float
+;                 ^ @number.float
 
 DATA.SET P:&HEAD+0x4 %LONG DATA.LONG(EA:&HEAD+0x4)&0xFFFFFF
 ;                                    ^ @constant.builtin
 
 List `main`
-;    ^ @symbol
+;    ^ @string.special.symbol
 
 &range = 'a'--'z'||'0'--'9'
 ;        ^ @character
@@ -34,6 +34,6 @@ Data.Set N: 0xffff800000 0y0011xx01xx&&a
 ;                                    ^ @operator
 
 WinPOS 0% 85% 100% 15%
-;             ^ @float
+;             ^ @number.float
 
 // vim: set ft=t32:

tests/query/highlights/t32/var.cmm

@@ -34,7 +34,7 @@ Var.Assign (*ap)[2..4] = &a
 Var.Assign sp = &s.n+offset
 ;          ^ @variable
 ;                ^ @variable
-;                  ^ @field
+;                  ^ @variable.member
 ;                    ^ @variable
 Var.Assign padd = (CAddition const * volatile)&d
 ;          ^ @variable