fix: update IDL highlights to reflect language changes (#984)

Fixes problem where backticks showed up in red in PDFs:

<img width="156" height="23" alt="image"
src="https://github.com/user-attachments/assets/5c54e238-5357-42dc-aa35-64bb57b9489a"
/>

now looks like:

<img width="163" height="27" alt="image"
src="https://github.com/user-attachments/assets/a92626de-6de1-4df1-bca1-e8f0ae3fef2f"
/>

---------

Signed-off-by: Derek Hower <[email protected]>
Co-authored-by: Paul Clarke <[email protected]>

Author: dhower-qc

backends/cfg_html_doc/ui/highlight.js

@@ -3530,7 +3530,7 @@
           name: "IDL",
           case_insensitive: !1,
           keywords:
-            "if else for return returns arguments builtin function enum bitfield",
+            "if else for return returns arguments builtin function enum bitfield generated struct",
           literal: "true false $pc $encoding",
           contains: [
             e.HASH_COMMENT_MODE,
@@ -3555,6 +3555,7 @@
             {
               className: "number",
               variants: [
+                { begin: /((MXLEN'(s?([bhodBHOD])?))[0-9xzXZa-fA-F_]+)/ },
                 { begin: /((\d+'(s?([bhodBHOD])?))[0-9xzXZa-fA-F_]+)/ },
                 { begin: /(('(s?([bhodBHOD])?))[0-9xzXZa-fA-F_]+)/ },
                 {

tools/ruby-gems/idl_highlighter/lib/idl_highlighter.rb

@@ -21,7 +21,7 @@ def self.keywords
         return @keywords unless @keywords.nil?
 
         @keywords = Set.new %w[
-          if else for return returns arguments description body function builtin enum bitfield
+          if else for return returns arguments description body function builtin enum bitfield generated struct
         ]
       end
 
@@ -46,9 +46,9 @@ def self.keywords_type
         rule %r/0x[0-9a-f]+[lu]*/i, Num::Hex
         rule %r/0[0-7]+[lu]*/i, Num::Oct
         rule %r{\d+}, Num::Integer
-        rule %r{(?:true|false|\$encoding|\$pc|\$signed|\$bits)}, Name::Builtin
+        rule %r{(?:true|false|\$encoding|\$pc|\$signed|\$bits|\$width|\$enum_size|\$enum_element_size|\$enum_to_a|\$enum|\$array_size)}, Name::Builtin
         rule %r{[.,;:\[\]\(\)\}\{]}, Punctuation
-        rule %r([~!%^&*+=\|?:<>/-]), Operator
+        rule %r([~!%^&*+=\|?:<>/`-]), Operator
         rule id do |m|
           name = m[0]