Document enum values

[Euphoria-MJansen]

Summary

Enum constants in the mrdocs DOM only expose initializer as written in the source. For enum constants with no explicit initializer, nothing is available at all.

Motivation

Consider:

#define BASE_VALUE 0x02000000

enum MyEnum {
    FirstValue = BASE_VALUE,  // initializer = "BASE_VALUE" (macro name, not resolved)
    SecondValue,              // no initializer at all
    ThirdValue,               // no initializer at all
};

The documentation generated for this enum shows (with a template modification):

Name	Value
FirstValue	BASE_VALUE
SecondValue	(empty)
ThirdValue	(empty)

What I would need:

Name	Value
FirstValue	33554432
SecondValue	33554433
ThirdValue	33554434

For protocol or wire-format enums where the numeric value is the essential piece of information, the unresolved macro name and missing implicit values are not useful.

Proposed change

Add a value field to enum-constant DOM objects containing the evaluated integer as a decimal string. The existing initializer field (source text) should remain for cases where showing the expression is preferred.

Example DOM (XML):

<enum-constant>
  <name>FirstValue</name>
  <initializer>BASE_VALUE</initializer>
  <value>33554432</value>
</enum-constant>
<enum-constant>
  <name>SecondValue</name>
  <value>33554433</value>
</enum-constant>

The Handlebars template could then use {{value}} (or fall back to {{initializer}}) to show the number.

---

Note: most of this ticket is generated using AI.