v3.3.8

• Added new DualMap<K, V> class in lib/src/dual_map.dart:

  • Bidirectional map maintaining two internal maps for O(1) lookup in both directions.
  • Supports insertion, removal, clear, and lookup by key or value.
  • Implements MapBase<K, V> interface.
  • Methods:
    • put(K key, V value): associates value with key, replacing existing mappings.
    • get(Object? key): returns value for key.
    • getKeyFromValue(V value): returns key for value.
    • putIfAbsent(K key, V Function() ifAbsent): inserts if key absent.
    • putValueIfAbsent(K key, V value): inserts value if key absent, returns bool.
    • remove(Object? key): removes key and reverse mapping.
    • clear(): clears all mappings.
  • Properties:
    • keys, values, entries provide iterable views.

• Updated lib/swiss_knife.dart:

  • Exported new src/dual_map.dart.