Add all missing docs

PkmnLib.Static/Species/Ability.cs

@@ -19,6 +19,9 @@ public interface IAbility : INamedValue
     /// </summary>
     IReadOnlyDictionary<StringKey, object?> Parameters { get; }
 
+    /// <summary>
+    /// Checks whether the ability has a specific flag. 
+    /// </summary>
     bool HasFlag(StringKey key);
 }
 
@@ -44,6 +47,9 @@ public class AbilityImpl : IAbility
     /// <inheritdoc />
     public IReadOnlyDictionary<StringKey, object?> Parameters { get; }
 
+    /// <summary>
+    /// A collection of arbitrary flags that can be used to mark the ability with specific properties.
+    /// </summary>
     public ImmutableHashSet<StringKey> Flags;
 
     /// <inheritdoc />