feat(compiler-core): support v-model shorthand for key and value with the same name

[L33Z22L11]

Since Vue 3.4, v-bind supports a shorthand when the key and value share the same name, but v-model does not. This inconsistency makes template code less concise.

This PR introduces a shorthand for v-model, allowing developers to omit the value when the key and value are the same.

<template>
    <!-- before -->
    <OrderToggle
        v-model:is-ascending="isAscending"
        v-model:sort-order="sortOrder"
        v-model:category="category"
        :categories
    />

    <!-- after -->
    <OrderToggle
        v-model:is-ascending
        v-model:sort-order
        v-model:category
        :categories
    />
</template>

An argument-less, no-expression v-model (e.g., <input v-model> without binding variable) will still result in an error.

[github-actions]

Size Report

Bundles

File	Size	Gzip	Brotli
runtime-dom.global.prod.js	100 kB	38.1 kB	34.4 kB
vue.global.prod.js	158 kB (+113 B)	58.3 kB (+29 B)	51.9 kB (-21 B)

Usages

Name	Size	Gzip	Brotli
createApp (CAPI only)	46.4 kB	18.2 kB	16.6 kB
createApp	54.4 kB	21.2 kB	19.4 kB
createSSRApp	58.6 kB	22.9 kB	20.9 kB
defineCustomElement	59.2 kB	22.7 kB	20.7 kB
overall	68.5 kB	26.4 kB	24 kB

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commit: e9fa047

[edison1105]

/ecosystem-ci run

[vue-bot]

📝 Ran ecosystem CI: Open

suite	result	latest scheduled
language-tools	❌ failure	✅ success
pinia	✅ success	✅ success
nuxt	✅ success	✅ success
test-utils	✅ success	✅ success
router	✅ success	✅ success
vant	✅ success	✅ success
primevue	✅ success	✅ success
quasar	✅ success	✅ success
radix-vue	✅ success	✅ success
vue-macros	✅ success	✅ success
vitepress	✅ success	✅ success
vuetify	✅ success	✅ success
vite-plugin-vue	✅ success	✅ success
vue-simple-compiler	✅ success	✅ success
vue-i18n	✅ success	✅ success
vueuse	✅ success	✅ success

[edison1105]

LGTM.
@L33Z22L11 Thanks.
I think we still need to update the documentation. https://vuejs.org/guide/essentials/template-syntax.html#same-name-shorthand