Add Vite configuration for TypeScript bundling

Created vite.config.ts with optimized settings for the Bookhoard project:
- Output directory: web/static/ (matches existing esbuild setup)
- Single entry point: web/src/main.ts
- Output file: main.js (preserves existing template references)
- ES2020 target for modern browser compatibility
- Source maps enabled for debugging
- esbuild minification for optimal bundle size
- emptyOutDir: false to preserve other static assets (htmx.min.js, CSS, images)

Configuration maintains the same build output structure as esbuild,
ensuring no changes needed to templates or deployment process.

vite.config.ts

@@ -0,0 +1,16 @@
+import { defineConfig } from "vite";
+export default defineConfig({
+  build: {
+    outDir: "web/static",
+    emptyOutDir: false,
+    rollupOptions: {
+      input: "web/src/main.ts",
+      output: {
+        entryFileNames: "main.js",
+      },
+    },
+    target: "es2020",
+    sourcemap: true,
+    minify: "esbuild",
+  },
+});