introduce endgames table

install/database_schema.sql

@@ -359,3 +359,19 @@ CREATE TABLE user_statistics (
     average_game_moves REAL GENERATED ALWAYS AS (CASE WHEN games_played != 0 THEN CAST(total_game_moves AS REAL) / games_played ELSE NULL END) STORED,
     PRIMARY KEY (user_id, variant_type)
 );
+
+
+DROP TABLE IF EXISTS endgames;
+CREATE TABLE endgames (
+    game_id       INTEGER  NOT NULL REFERENCES games (id),
+    turn          SMALLINT NOT NULL,
+    /**
+    * We want to be able to store probabilities for different actions that can be taken.
+    * We use the same encoding as in the game_actions table, except that for clues, we do not store values.
+    */
+    action_type   SMALLINT NOT NULL,
+    action_target SMALLINT NOT NULL,
+    enumerator    INTEGER  NOT NULL,
+    denominator   INTEGER  NOT NULL,
+    PRIMARY KEY (game_id, turn, action_type, action_target)
+);