feat(highlights)!: enforce documented captures (#6232)

Problem: Allowing undocumented "secret" (sub)captures makes it harder
to write comprehensive colorschemes and catch inconsistent captures.

Solution: Only allow captures listed in CONTRIBUTING.md. Add useful
(cross-language) subcaptures and drop language-specific or too niche
ones.

Follow-up: Adding further `*.builtin` captures and changing queries to
use them.

Language-specific subcaptures should instead be added in user config or
a custom language plugin.

queries/latex/highlights.scm

@@ -41,16 +41,16 @@
 
 ; General environments
 (begin
-  command: _ @markup.environment
+  command: _ @module
   name:
     (curly_group_text
-      (text) @markup.environment.name))
+      (text) @label))
 
 (end
-  command: _ @markup.environment
+  command: _ @module
   name:
     (curly_group_text
-      (text) @markup.environment.name))
+      (text) @label))
 
 ; Definitions and references
 (new_command_definition
@@ -77,7 +77,7 @@
   command: _ @function.macro
   name:
     (curly_group_text
-      (_) @markup.environment.name))
+      (_) @label))
 
 (paired_delimiter_definition
   command: _ @function.macro
@@ -260,8 +260,8 @@
   (begin
     name:
       (curly_group_text
-        (text) @markup.environment.name)
-    (#any-of? @markup.environment.name "frame"))
+        (text) @label)
+    (#any-of? @label "frame"))
   .
   (curly_group
     (_) @markup.heading))