fix: make vite a dynamic import and declare it as optional peer dependency - #259

unplugin-solid had a static top-level import { version } from "vite" that caused a hard runtime failure in strict dependency environments (Yarn PnP) when consumers weren't using Vite — the module would fail to load even for Rollup/esbuild/webpack users.

Changes

• src/core/index.ts: Replace static import { version } from "vite" with a dynamic await import("vite") scoped to the Vite-specific config hook where it's actually needed, with a clear error message if the import fails
• package.json: Declare vite >=4 as an optional peer dependency via peerDependenciesMeta

-import { version } from "vite";
 // ...
 vite: {
   async config(userConfig, { command }) {
     // ...
+    const { version } = await import("vite").catch(() => {
+      throw new Error("[unplugin-solid] Failed to import 'vite'. Make sure 'vite' is installed.");
+    });
     const isViteGreaterThan6 = +version.split(".")[0] >= 6;