frontend: refactor build viewer a bit more

frontend/composables/useBuilds.ts

@@ -0,0 +1,32 @@
+/**
+ * Composable for managing build data with automatic trimming
+ * Handles deep cloning and tree manipulation
+ */
+import { deepClone } from '~/utils/helpers'
+import { trimBuilds, trimLateGameItems } from '~/utils/buildHelpers'
+
+export const useBuilds = (buildsProp: Ref<Builds>) => {
+  const builds = ref<Builds>(deepClone(buildsProp.value))
+
+  function trimBuildData(): void {
+    trimBuilds(builds.value)
+    trimLateGameItems(builds.value)
+  }
+
+  // Watch for changes and rebuild
+  watch(
+    () => buildsProp.value,
+    (newBuilds) => {
+      builds.value = deepClone(newBuilds)
+      trimBuildData()
+    },
+    { deep: true }
+  )
+
+  // Initial trim on mount
+  onMounted(() => {
+    trimBuildData()
+  })
+
+  return { builds }
+}