feat: add contentAddressedStatic to Vite plugin config

Port the contentAddressedStatic option to FreshViteConfig so it works
with the modern App/Vite path (not just the legacy Builder API).
Static files matching the glob patterns are marked immutable in the
snapshot, enabling content-hash caching that survives deploys.

Author: bartlomieju

docs/latest/concepts/static-files.md

@@ -135,14 +135,22 @@ that should use their **content hash** as the cache-bust key instead of the
 build ID. The URL only changes when the file content changes — surviving deploys
 unchanged.
 
-```ts dev.ts
-import { Builder } from "fresh/dev";
+```ts vite.config.ts
+import { defineConfig } from "vite";
+import { fresh } from "@fresh/plugin-vite";
 
-const builder = new Builder({
-  contentAddressedStatic: ["**/*.wasm", "**/*.bin"],
+export default defineConfig({
+  plugins: [
+    fresh({
+      contentAddressedStatic: ["**/*.wasm", "**/*.bin"],
+    }),
+  ],
 });
 ```
 
+> [info]: If you're using the [Builder](/docs/advanced/builder) API, the same
+> option is available on the `Builder` constructor.
+
 With this config, `asset("/module.wasm")` produces a URL like
 `/module.wasm?__frsh_c=<content-hash>` instead of
 `/module.wasm?__frsh_c=<build-id>`. The middleware serves it with a one-year

packages/plugin-vite/src/mod.ts

@@ -66,6 +66,7 @@ export function fresh(config?: FreshViteConfig): Plugin[] {
     islandSpecifiers: new Map(),
     namer: new UniqueNamer(),
     checkImports: config?.checkImports ?? [],
+    contentAddressedStatic: config?.contentAddressedStatic ?? [],
   };
 
   fConfig.checkImports.push((id, env) => {

packages/plugin-vite/src/plugins/server_snapshot.ts

@@ -21,6 +21,7 @@ import {
   type ResolvedFreshViteConfig,
 } from "../utils.ts";
 import * as path from "@std/path";
+import { globToRegExp } from "@std/path";
 import { getBuildId } from "./build_id.ts";
 
 export function serverSnapshot(options: ResolvedFreshViteConfig): Plugin[] {
@@ -276,6 +277,12 @@ export function serverSnapshot(options: ResolvedFreshViteConfig): Plugin[] {
 
             // Walk all static directories. First directory wins for
             // duplicate pathnames.
+            const caRegexps = options.contentAddressedStatic.map((p) =>
+              globToRegExp(p, { extended: true, globstar: true })
+            );
+            const isContentAddressed = (pathname: string) =>
+              caRegexps.some((re) => re.test(pathname));
+
             const seenStaticPaths = new Set<string>();
             for (const dir of options.staticDir) {
               if (!(await fsAdapter.isDirectory(dir))) continue;
@@ -312,6 +319,7 @@ export function serverSnapshot(options: ResolvedFreshViteConfig): Plugin[] {
                   filePath,
                   hash: null,
                   pathname: relative,
+                  immutable: isContentAddressed(relative) || undefined,
                 });
 
                 if (path.basename(relative) === "index.html") {

packages/plugin-vite/src/utils.ts

@@ -69,14 +69,30 @@ export interface FreshViteConfig {
    * are not imported in Islands running in the browser.
    */
   checkImports?: ImportCheck[];
+  /**
+   * Glob patterns for static files that should use content-hash
+   * caching instead of build ID. Matching files get immutable cache
+   * headers and their `asset()` URLs only change when the file
+   * content changes — surviving deploys unchanged.
+   *
+   * Useful for large assets like WASM binaries, fonts, or media
+   * that rarely change between deploys.
+   *
+   * @example ["**\/*.wasm", "**\/*.bin"]
+   */
+  contentAddressedStatic?: string[];
 }
 
 export type ResolvedFreshViteConfig =
   & Required<
-    Omit<FreshViteConfig, "islandSpecifiers" | "staticDir">
+    Omit<
+      FreshViteConfig,
+      "islandSpecifiers" | "staticDir" | "contentAddressedStatic"
+    >
   >
   & {
     staticDir: string[];
     islandSpecifiers: Map<string, string>;
     namer: UniqueNamer;
+    contentAddressedStatic: string[];
   };