fix(vite): alias vue through resolve.alias so the Vue flavor builds under rolldown - #11431

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What is the current behavior?

vueConfig aliases vue to nativescript-vue through @rollup/plugin-alias (enforce: 'pre'). With Vite 8 / rolldown the bare replacement resolves to the package directory, and every build fails on the from "vue" import that @vitejs/plugin-vue injects into each SFC:

[UNLOADABLE_DEPENDENCY] Could not load node_modules/nativescript-vue
 1 │ import { defineComponent as _defineComponent } from "vue";
   │                                                     ╰──── Is a directory (os error 21)

An exports map in nativescript-vue and the dedupe entry in base.ts do not change the outcome.

What is the new behavior?

The alias moves to Vite's resolve.alias ({ find: 'vue', replacement: 'nativescript-vue' }), which keeps the same exact-and-subpath matching and resolves the bare package correctly under rolldown. The set-value entry is dropped from the Vue layer because base.ts already aliases it. configuration/vue.spec.ts pins the shape.

Verified with the repro from nativescript-vue/nativescript-vue#1160: vite build -- --env.ios and ns prepare ios pass with this config, against both a local runtime and the published nativescript-vue 3.1.1.

Fixes #11429 (part 1; the HMR symlink problem in part 2 is #11430).

npx vitest run in packages/vite: the only failures are the pre-existing typescript-optional.spec.ts cases, which need a built package.