fix: support map and set data structure in keys, values fn

[hg-pyun]

Fixes #361

Summary

Add Map and Set support to the keys and values functions, following the established pattern in entries.ts.

Changes

• keys: Now supports Map (yields keys) and Set (yields values, as Set keys equal values).
• values: Now supports Map (yields values) and Set (yields values).
• Runtime Tests: Added comprehensive tests for Map and Set support.
• Type-check Tests: Added tests to ensure proper type inference is maintained.

Motivation

This change brings consistency across the entries, keys, and values functions. Previously, only entries supported Map and Set data structures (#362), while keys and values were limited to plain objects.

Usage

// keys - Map
[...keys(new Map([["a", 1], ["b", 2]]))] 
// ["a", "b"]

// keys - Set
[...keys(new Set([1, 2, 3]))] 
// [1, 2, 3]

// values - Map
[...values(new Map([["a", 1], ["b", 2]]))] 
// [1, 2]

// values - Set
[...values(new Set([1, 2, 3]))] 
// [1, 2, 3]

Type Safety

Full type inference is preserved:

keys(Map<K, V>) returns Generator<K, void>

keys(Set<V>) returns Generator<V, void>

values(Map<K, V>) returns Generator<V, void>

values(Set<V>) returns Generator<V, void>

⚠️ Breaking Changes

None. Existing code using keys and values with plain objects continues to work identically.

[ppeeou]

lgtm 🚀