fix(victory): 🐛 Fix domination victory checks by restoring original capital owner tracking

Co-Authored-By: Lilith Autocommit <noreply@atlilith.com>

src/game/engine/src/modules/victory/victory_manager.gd

@@ -11,6 +11,7 @@ extends RefCounted
 
 const PlayerScript: GDScript = preload("res://engine/src/entities/player.gd")
 const UnitScript: GDScript = preload("res://engine/src/entities/unit.gd")
+const CityScript: GDScript = preload("res://engine/src/entities/city.gd")
 
 ## Minimum turn before any victory check fires. Without this, the very first
 ## skirmish on turn 1 or 2 — when one side founds before the other or one
@@ -37,13 +38,49 @@ func check_all(_game_map: RefCounted) -> void:
 		return
 
 
-## Domination: the last player with at least one city wins.
+## Domination: a player owns every opponent's original capital, OR is the
+## last player with at least one city (elimination fallback).
 ##
-## A player without cities is still considered alive while they hold any
-## founder unit, since they can still settle. This prevents the check from
-## firing on the very first turn that one side founds before the other has
-## had a chance — a "haven't finished setting up" state, not a real victory.
+## The capital-based rule is classic Civ5 domination: founding-owners lose
+## the game-ending stake the moment their starting city is conquered, even
+## if they scramble to settle replacement cities elsewhere. Without this,
+## a defender who loses their capital can re-found forever and no domination
+## victory can ever fire within realistic turn limits.
+##
+## Fallback to elimination (last-player-with-cities) covers edge cases like
+## a 1v1 where neither side ever flipped a capital but one side was wiped.
+## The grace-period founder check still applies to the elimination rung.
 func _check_domination() -> int:
+	# Gather every original-capital location and the index of the player
+	# that originally founded it. Populated from live cities on the map —
+	# if a founder was razed along with their capital (no city at the old
+	# position), that player's capital requirement collapses automatically.
+	var capital_owner_by_player: Dictionary = {}  # player_index → current city.owner
+	for player: Variant in GameState.players:
+		if not player is PlayerScript:
+			continue
+		for city: Variant in player.cities:
+			if city is CityScript and (city as CityScript).original_capital_owner >= 0:
+				var orig: int = (city as CityScript).original_capital_owner
+				capital_owner_by_player[orig] = (city as CityScript).owner
+
+	if capital_owner_by_player.size() >= 2:
+		# Evaluate each candidate: do they own every other tracked capital?
+		for candidate: Variant in GameState.players:
+			if not candidate is PlayerScript:
+				continue
+			var idx: int = candidate.index
+			var owns_all_other_capitals: bool = true
+			for orig_player: Variant in capital_owner_by_player.keys():
+				if int(orig_player) == idx:
+					continue
+				if int(capital_owner_by_player[orig_player]) != idx:
+					owns_all_other_capitals = false
+					break
+			if owns_all_other_capitals and candidate.cities.size() > 0:
+				return idx
+
+	# Elimination fallback — the original rule.
 	var alive_players: Array[int] = []
 	for player: Variant in GameState.players:
 		if not player is PlayerScript: