rename gauntlet→candy_survival + rewrite Candy Survival per boss design

- Rename enum GAUNTLET→CANDY_SURVIVAL, all gauntlet_*→candy_survival_*
- Rename files: gauntlet_manager→candy_survival_manager, candy_cannon→candy_survival_npc, gauntlet.tscn→candy_survival.tscn
- Rewrite candy_survival_manager.gd: blueprints, candy stack, Mekton delivery, Sugar Rush, knock/ghost charges, sticky-as-wall
- Update player_movement_manager.gd: smack→knock system, ghost integration
- All Candy Survival issues (#54-57, #65-70) retitled per boss design
- Shared managers (goals_cycle, goal, player_race, playerboard, turn) untouched

scripts/game_mode.gd

@@ -1,7 +1,7 @@
 extends RefCounted
 class_name GameMode
 
-enum Mode { FREEMODE = 0, STOP_N_GO = 1, GAUNTLET = 2 }
+enum Mode { FREEMODE = 0, STOP_N_GO = 1, CANDY_SURVIVAL = 2 }
 
 static func from_string(mode: String) -> Mode:
 	match mode:
@@ -9,8 +9,8 @@ static func from_string(mode: String) -> Mode:
 			return Mode.FREEMODE
 		"Stop n Go":
 			return Mode.STOP_N_GO
-		"Candy Pump Survival":
-			return Mode.GAUNTLET
+		"Candy Survival":
+			return Mode.CANDY_SURVIVAL
 	return Mode.FREEMODE
 
 static func mode_to_string(mode: Mode) -> String:
@@ -19,13 +19,13 @@ static func mode_to_string(mode: Mode) -> String:
 			return "Freemode"
 		Mode.STOP_N_GO:
 			return "Stop n Go"
-		Mode.GAUNTLET:
-			return "Candy Pump Survival"
+		Mode.CANDY_SURVIVAL:
+			return "Candy Survival"
 		_:
 			return "Freemode"
 
 static func is_restricted(mode: Mode) -> bool:
-	return mode == Mode.STOP_N_GO or mode == Mode.GAUNTLET
+	return mode == Mode.STOP_N_GO or mode == Mode.CANDY_SURVIVAL
 
 static func get_all_modes() -> Array[String]:
-	return ["Freemode", "Stop n Go", "Candy Pump Survival"]
+	return ["Freemode", "Stop n Go", "Candy Survival"]