Create store for current milestoneId

src/stores/currentMilestone.ts

+import { ref } from 'vue'
+import { defineStore } from 'pinia'
+
+export const useMilestoneStore = defineStore('milestoneId', () => {
+  const milestoneId = ref<number>();
+
+  function setMilestoneId(id: number){
+    milestoneId.value = id
+  }
+
+  return { milestoneId, setMilestoneId}
+})
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