`pluralize` schema and implementation missing `two`, `few`, `many` branches (v0_9 spec non-conformance)

[BBC6BAE9]

Bug

PluralizeFunction only implements zero, one, and other. The v0_9 spec defines six CLDR plural categories: zero, one, two, few, many, other. The missing three branches make pluralize non-functional for Arabic, Welsh, Polish, Russian, and many other languages.

Spec reference

From basic_catalog.json (v0_9):

"two":  { "description": "String for the 'two' category (used in Arabic, Welsh, etc.)." },
"few":  { "description": "String for the 'few' category (e.g., small groups in Slavic languages)." },
"many": { "description": "String for the 'many' category (e.g., large groups in various languages)." }

Current implementation

packages/genui/lib/src/catalog/basic_functions.dart

// argumentSchema — missing two/few/many entirely
Schema get argumentSchema => S.object(
  properties: {
    'count': S.number(),
    'zero': S.string(),
    'one': S.string(),
    'other': S.string(),   // two, few, many not declared
  },
);

// executeSync — no branch for two/few/many
if (count == 0 && args.containsKey('zero')) return args['zero'];
if (count == 1 && args.containsKey('one')) return args['one'];
return args['other'] ?? '';  // everything else falls here

Comparison with WebCore

WebCore (basic_functions.ts) hard-codes en-US in Intl.PluralRules, which is wrong for non-English locales, but the CLDR category lookup itself works — two/few/many are reachable via the args[rule] lookup. genui does not reach this bar: those categories are absent from both the schema and the implementation.

Related

#902 — pluralize reads wrong key args["count"] instead of args["value"]

Both issues need to be fixed together for pluralize to be spec-conformant.