Fixed rail network path length limit and readded tests for it (#4406)

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**Add approved & assigned issue number here:**

Resolves #4396 

## Description:

Makes the max rail length 1.4142 * the max station radius to be minimum
amount outside of the factory effect radius.

Bug:
<img width="1921" height="1078" alt="image"
src="https://github.com/user-attachments/assets/91b3b3fa-037a-4d9a-b06b-afe2fe2c8ea8"
/>
Fixed:
<img width="1922" height="1079" alt="image"
src="https://github.com/user-attachments/assets/3719cf73-bc41-494f-9d86-548f308f5896"
/>


## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory

## Please put your Discord username so you can be contacted if a bug or
regression is found:

tktk1234567

tests/core/game/RailNetwork.test.ts

@@ -71,6 +71,7 @@ describe("RailNetworkImpl", () => {
       config: () => ({
         trainStationMaxRange: () => 80,
         trainStationMinRange: () => 10,
+        railroadMaxSize: () => 100,
       }),
       x: vi.fn(() => 0),
       y: vi.fn(() => 0),
@@ -249,11 +250,7 @@ describe("RailNetworkImpl", () => {
       pathService.findTilePath.mockReturnValue(mockPath);
 
       game.nearbyUnits.mockReturnValue([
-        {
-          unit: neighborStation.unit,
-          distSquared: 400,
-          euclideanDist: Math.sqrt(400),
-        },
+        { unit: neighborStation.unit, distSquared: 400 },
       ]);
 
       const result = network.computeGhostRailPaths(UnitType.City, tile);
@@ -272,11 +269,7 @@ describe("RailNetworkImpl", () => {
 
       // distSquared = 50 <= minRange^2 (10^2 = 100)
       game.nearbyUnits.mockReturnValue([
-        {
-          unit: neighborStation.unit,
-          distSquared: 50,
-          euclideanDist: Math.sqrt(50),
-        },
+        { unit: neighborStation.unit, distSquared: 50 },
       ]);
 
       const result = network.computeGhostRailPaths(UnitType.City, tile);
@@ -290,8 +283,26 @@ describe("RailNetworkImpl", () => {
 
       stationManager.findStation.mockReturnValue(null);
 
+      game.nearbyUnits.mockReturnValue([{ unit: { id: 1 }, distSquared: 400 }]);
+
+      const result = network.computeGhostRailPaths(UnitType.City, tile);
+      expect(result).toEqual([]);
+    });
+
+    test("skips paths that exceed max railroad size", () => {
+      const tile = 42 as any;
+      const railGridMock = { query: vi.fn(() => new Set()) };
+      (network as any).railGrid = railGridMock;
+
+      const neighborStation = createMockStation(1);
+      neighborStation.tile.mockReturnValue(100);
+      stationManager.findStation.mockReturnValue(neighborStation);
+
+      // Path length >= railroadMaxSize (100)
+      pathService.findTilePath.mockReturnValue(new Array(100));
+
       game.nearbyUnits.mockReturnValue([
-        { unit: { id: 1 }, distSquared: 400, euclideanDist: Math.sqrt(400) },
+        { unit: neighborStation.unit, distSquared: 400 },
       ]);
 
       const result = network.computeGhostRailPaths(UnitType.City, tile);
@@ -303,19 +314,11 @@ describe("RailNetworkImpl", () => {
       const railGridMock = { query: vi.fn(() => new Set()) };
       (network as any).railGrid = railGridMock;
 
-      const neighbors: Array<{
-        unit: any;
-        distSquared: number;
-        euclideanDist: number;
-      }> = [];
+      const neighbors: Array<{ unit: any; distSquared: number }> = [];
       for (let i = 0; i < 7; i++) {
         const station = createMockStation(i);
         station.tile.mockReturnValue(100 + i);
-        neighbors.push({
-          unit: station.unit,
-          distSquared: 400 + i,
-          euclideanDist: Math.sqrt(400 + i),
-        });
+        neighbors.push({ unit: station.unit, distSquared: 400 + i });
       }
 
       stationManager.findStation.mockImplementation((unit: any) => {