adding classification and division yard updates, train collisions, engine and car updates, turnout improvements.

test/advance.test.ts

@@ -257,7 +257,7 @@ describe('Mainline Phase (§8)', () => {
         id: `t${i}`,
         trainNumber: spec.n,
         trainIsExtra: spec.extra,
-        engineFront: true,
+        engineAt: 0,
         consist: [],
         direction: 'east',
         position: { at: 'divisionPoint', side: 'west' },
@@ -287,7 +287,7 @@ describe('collisions are automatic (Gap 2)', () => {
       id,
       trainNumber: 2,
       trainIsExtra: false,
-      engineFront: true,
+      engineAt: 0,
       consist: [{ type: 'coach', loaded: true }],
       direction: 'east',
       position: { at: 'mainline', index: 1 },
@@ -328,7 +328,7 @@ describe('collisions are automatic (Gap 2)', () => {
       id: 'x',
       trainNumber: 8,
       trainIsExtra: false,
-      engineFront: true,
+      engineAt: 0,
       consist: [
         { type: 'hopper', loaded: true },
         { type: 'caboose', loaded: true },
@@ -359,7 +359,7 @@ describe('the Superintendent clearance interrupt (§8.1)', () => {
       id: 'ahead',
       trainNumber: 4,
       trainIsExtra: false,
-      engineFront: true,
+      engineAt: 0,
       consist: [],
       direction: 'east',
       position: { at: 'mainline', index: 1 },
@@ -379,7 +379,7 @@ describe('the Superintendent clearance interrupt (§8.1)', () => {
       id: 'behind',
       trainNumber: 2,
       trainIsExtra: false,
-      engineFront: true,
+      engineAt: 0,
       consist: [],
       direction: 'east',
       position: { at: 'divisionPoint', side: 'west' },
@@ -402,7 +402,7 @@ describe('the Superintendent clearance interrupt (§8.1)', () => {
       id: 'oncoming',
       trainNumber: 3,
       trainIsExtra: false,
-      engineFront: true,
+      engineAt: 0,
       consist: [],
       direction: 'west',
       position: { at: 'mainline', index: 1 },
@@ -421,7 +421,7 @@ describe('the Superintendent clearance interrupt (§8.1)', () => {
       id: 'waiting',
       trainNumber: 2,
       trainIsExtra: false,
-      engineFront: true,
+      engineAt: 0,
       consist: [],
       direction: 'east',
       position: { at: 'divisionPoint', side: 'west' },