chore(component): prepare OperationalButton

fix #30

src/components/CalculatorContainer/OperationalButton.test.ts

@@ -6,7 +6,7 @@ describe("Component: CalculatorContainer/OperationalButton", () => {
 	it("can emit custom value", async() => {
 		const wrapper = shallowMount(Component, {
 			"props": {
-				"value": 1
+				"value": "+"
 			}
 		})
 		const operationalBtn = wrapper.find("button.operational-button")

src/components/CalculatorContainer/OperationalButton.vue

@@ -0,0 +1,25 @@
+<script setup lang="ts">
+type Operations = "+"|"-"|"×"|"÷"
+interface Props {
+	value: Operations
+}
+const props = defineProps<Props>()
+
+interface CustomEvents {
+	(event: "appendToScreen", valueToAppend: string): void
+}
+const emit = defineEmits<CustomEvents>()
+
+function appendToScreen() {
+	emit("appendToScreen", props.value)
+}
+</script>
+
+<template>
+	<button class="operational-button" @click="appendToScreen">
+		{{ props.value }}
+	</button>
+</template>
+
+<style scoped lang="scss">
+</style>