Add BehaviorSupportProfile to pygambit

ChangeLog

@@ -1,3 +1,12 @@
+## [17.0.0-beta.1] - unreleased
+
+### Added
+- Added `BehaviorSupportProfile` to `pygambit`.
+
+### Changed
+- Revised `StrategySupportProfile` to expose a slimmer set of operations, and
+  implement `StrategySupport` as an immutable snapshot.
+
 ## [17.0.0-alpha.2] - 2026-08-21
 
 ### Added

doc/pygambit.api.rst

@@ -220,6 +220,7 @@ Player behavior
    Game.mixed_behavior_profile
    Game.random_behavior_profile
    Game.strategy_support_profile
+   Game.behavior_support_profile
 
 
 Representation of strategic behavior
@@ -336,6 +337,56 @@ Probability distributions over behavior
    NodeValuesVector
 
 
+Representation of supports
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. currentmodule:: pygambit.gambit
+
+Subsets of strategies
+......................
+
+.. autosummary::
+   :toctree: api/
+
+   StrategySupportProfile
+   StrategySupportProfile.game
+   StrategySupportProfile.__iter__
+   StrategySupportProfile.__getitem__
+   StrategySupportProfile.__setitem__
+   StrategySupportProfile.copy
+   StrategySupportProfile.restrict
+   StrategySupportProfile.is_dominated
+
+   StrategySupport
+   StrategySupport.player
+   StrategySupport.__iter__
+   StrategySupport.__contains__
+
+Subsets of actions
+...................
+
+.. autosummary::
+   :toctree: api/
+
+   BehaviorSupportProfile
+   BehaviorSupportProfile.game
+   BehaviorSupportProfile.__iter__
+   BehaviorSupportProfile.__getitem__
+   BehaviorSupportProfile.__setitem__
+   BehaviorSupportProfile.copy
+   BehaviorSupportProfile.is_reachable
+
+   BehaviorSupport
+   BehaviorSupport.player
+   BehaviorSupport.__iter__
+   BehaviorSupport.__getitem__
+
+   ActionSupport
+   ActionSupport.infoset
+   ActionSupport.__iter__
+   ActionSupport.__contains__
+
+
 Computation on supports
 ~~~~~~~~~~~~~~~~~~~~~~~