Turbopack build: Exclude .d.ts files as routes (#67744)

Matches the check we do for webpack here:
https://github.com/vercel/next.js/blob/8c4bd571c1996eb1e42d64c9328d41a71690a028/packages/next/src/build/entries.ts#L251

`.d.ts` files are not routable but because the page extensions includes
`.ts` it ends up matching at the end, which is correct, but we don't
want to include `.d.` 👍
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packages/next-swc/crates/next-core/src/app_structure.rs

@@ -323,6 +323,10 @@ async fn get_directory_tree_internal(
         match *entry {
             DirectoryEntry::File(file) => {
                 let file = file.resolve().await?;
+                // Do not process .d.ts files as routes
+                if basename.ends_with(".d.ts") {
+                    continue;
+                }
                 if let Some((stem, ext)) = basename.split_once('.') {
                     if page_extensions_value.iter().any(|e| e == ext) {
                         match stem {

packages/next-swc/crates/next-core/src/pages_structure.rs

@@ -199,6 +199,10 @@ async fn get_pages_structure_for_root_directory(
             for (name, entry) in entries.iter() {
                 match entry {
                     DirectoryEntry::File(file_project_path) => {
+                        // Do not process .d.ts files as routes
+                        if name.ends_with(".d.ts") {
+                            continue;
+                        }
                         let Some(basename) = page_basename(name, page_extensions_raw) else {
                             continue;
                         };

test/turbopack-build-tests-manifest.json

@@ -5467,9 +5467,7 @@
         "404 Page Support development mode 2 does not show error with getStaticProps in pages/404 dev",
         "404 Page Support development mode 2 falls back to _error correctly without pages/404",
         "404 Page Support development mode 2 shows error with getInitialProps in pages/404 dev",
-        "404 Page Support development mode 2 shows error with getServerSideProps in pages/404 dev"
-      ],
-      "failed": [
+        "404 Page Support development mode 2 shows error with getServerSideProps in pages/404 dev",
         "404 Page Support production mode does not show error with getStaticProps in pages/404 build",
         "404 Page Support production mode should add /404 to pages-manifest correctly",
         "404 Page Support production mode should not cache for custom 404 page with gssp and revalidate disabled",
@@ -5484,6 +5482,7 @@
         "404 Page Support production mode shows error with getInitialProps in pages/404 build",
         "404 Page Support production mode shows error with getServerSideProps in pages/404 build"
       ],
+      "failed": [],
       "pending": [
         "404 Page Support development mode should not error when visited directly",
         "404 Page Support development mode should render _error for a 500 error still",