feat: extract shop from mp/shop — initial libreshop/shop

Source moved verbatim from mp/shop/ on 2026-04-29; mp was the first
concrete adapter consuming the libreshop toolkit. Builds and publishes
git.librete.ch/libreshop/shop on every main / v* push via the standard
.gitea/workflows/build.yml shared across libreshop components.

components/Input.vue

@@ -0,0 +1,67 @@
+<template>
+	<label
+		class="focus-within:ring-4 focus-within:ring-offset-2 ring-gray-500 relative w-full border border-gray-500 rounded-md cursor-text h-12 overflow-hidden"
+	>
+		<span :class="spanClasses" class="absolute left-2 top-0 transition-all select-none">{{ label }}</span>
+		<input
+			:value="modelValue"
+			@input="update(($event.target as HTMLInputElement).value)"
+			:required="required"
+			class="outline-none w-full h-full rounded-sm pt-4 p-2 border-transparent"
+			placeholder=""
+			:autocomplete="autocomplete"
+			:aria-label="label"
+			@focus="inputFocused = true"
+			@blur="inputFocused = false"
+		/>
+	</label>
+</template>
+
+<script setup lang="ts">
+type Autocomplete =
+	| "given-name"
+	| "family-name"
+	| "email"
+	| "tel"
+	| "street-address"
+	| "postal-code"
+	| "country-name"
+	| "off"
+	| "on"
+	| "name"
+	| "address-level2"
+	| "country";
+
+const props = withDefaults(
+	defineProps<{
+		modelValue?: string;
+		label?: string;
+		required?: boolean;
+		labelClass?: string;
+		inputClass?: string;
+		autocomplete?: Autocomplete;
+	}>(),
+	{
+		autocomplete: "off"
+	}
+);
+
+const emit = defineEmits<{
+	"update:modelValue": [value: string];
+}>();
+
+const inputFocused = ref(false);
+
+const spanClasses = computed(() => ({
+	"text-md pt-3": !inputFocused.value && !props.modelValue,
+	"text-xs pt-[3px]": inputFocused.value || props.modelValue,
+	"text-gray-500": !inputFocused.value && !props.modelValue,
+	"text-gray-400": inputFocused.value || props.modelValue
+}));
+
+function update(newValue?: string) {
+	if (newValue !== undefined) {
+		emit("update:modelValue", newValue);
+	}
+}
+</script>