refactor: split engine methods into separate files

client/src/composables/engine/startStop.ts

@@ -1,4 +1,4 @@
-export default function (): void {
+export function start(): void {
     if (this.isActive.value && !this.shouldStop.value) {
         console.warn('attempt to start already running engine!')
         return
@@ -7,3 +7,10 @@ export default function (): void {
     this.shouldStop.value = false
     console.log('start engine')
 }
+
+export function stop(): void {
+    if (this.isActive.value) {
+        this.shouldStop.value = true
+        console.log('shut down engine')
+    }
+}

client/src/composables/useEngine.ts

@@ -1,6 +1,6 @@
 import { useState } from '#app'
 import { Ref } from 'vue'
-import start from '@/composables/engine/start'
+import { start, stop } from '@/composables/engine/startStop'
 
 interface EngineContext {
     isActive: Ref<boolean>
@@ -20,11 +20,6 @@ export default (): useEngine => {
 
     return {
         start: () => start.apply(context),
-        stop: (): void => {
+        stop: () => stop.apply(context),
-            if (context.isActive.value) {
-                context.shouldStop.value = true
-                console.log('shut down engine')
-            }
-        },
     }
 }