[autofix.ci] apply automated fixes

JSC only performs Tail Call Optimization (TCO) in strict mode. The REPL
evaluated code as a sloppy mode Program, which prevented TCO and caused
`RangeError: Maximum call stack size exceeded` for tail-recursive functions.

Prepend `"use strict";` to the evaluated source code so JSC can apply
TCO. Top-level `var` declarations still become global properties in
strict mode, so REPL variable persistence is unaffected.

Closes #27488

Co-Authored-By: Claude <noreply@anthropic.com>

docs/bundler/executables.mdx

@@ -228,16 +228,16 @@ To build for macOS x64:
 
 The order of the `--target` flag does not matter, as long as they're delimited by a `-`.
 
-| --target              | Operating System | Architecture | Modern | Baseline | Libc  |
-| --------------------- | ---------------- | ------------ | ------ | -------- | ----- |
-| bun-linux-x64         | Linux            | x64          | ✅     | ✅       | glibc |
-| bun-linux-arm64       | Linux            | arm64        | ✅     | N/A      | glibc |
-| bun-windows-x64       | Windows          | x64          | ✅     | ✅       | -     |
-| bun-windows-arm64     | Windows          | arm64        | ✅     | N/A      | -     |
-| bun-darwin-x64        | macOS            | x64          | ✅     | ✅       | -     |
-| bun-darwin-arm64      | macOS            | arm64        | ✅     | N/A      | -     |
-| bun-linux-x64-musl    | Linux            | x64          | ✅     | ✅       | musl  |
-| bun-linux-arm64-musl  | Linux            | arm64        | ✅     | N/A      | musl  |
+| --target             | Operating System | Architecture | Modern | Baseline | Libc  |
+| -------------------- | ---------------- | ------------ | ------ | -------- | ----- |
+| bun-linux-x64        | Linux            | x64          | ✅     | ✅       | glibc |
+| bun-linux-arm64      | Linux            | arm64        | ✅     | N/A      | glibc |
+| bun-windows-x64      | Windows          | x64          | ✅     | ✅       | -     |
+| bun-windows-arm64    | Windows          | arm64        | ✅     | N/A      | -     |
+| bun-darwin-x64       | macOS            | x64          | ✅     | ✅       | -     |
+| bun-darwin-arm64     | macOS            | arm64        | ✅     | N/A      | -     |
+| bun-linux-x64-musl   | Linux            | x64          | ✅     | ✅       | musl  |
+| bun-linux-arm64-musl | Linux            | arm64        | ✅     | N/A      | musl  |
 
 <Warning>
   On x64 platforms, Bun uses SIMD optimizations which require a modern CPU supporting AVX2 instructions. The `-baseline`

src/bun.js/bindings/bindings.cpp

@@ -6165,7 +6165,7 @@ extern "C" JSC::EncodedJSValue Bun__REPL__evaluate(
     auto& vm = JSC::getVM(globalObject);
     auto scope = DECLARE_TOP_EXCEPTION_SCOPE(vm);
 
-    WTF::String source = WTF::String::fromUTF8(std::span { sourcePtr, sourceLen });
+    WTF::String source = makeString("\"use strict\";"_s, WTF::String::fromUTF8(std::span { sourcePtr, sourceLen }));
     WTF::String filename = filenameLen > 0
         ? WTF::String::fromUTF8(std::span { filenamePtr, filenameLen })
         : "[repl]"_s;

test/regression/issue/27488.test.ts

@@ -0,0 +1,22 @@
+import { expect, test } from "bun:test";
+import { bunEnv, bunExe } from "harness";
+
+// https://github.com/oven-sh/bun/issues/27488
+// Tail calls in the REPL should work (requires strict mode for JSC TCO)
+test("REPL supports tail call optimization", async () => {
+  await using proc = Bun.spawn({
+    cmd: [bunExe(), "repl", "-e", "const foo = n => n <= 0 ? n : foo(n-1); console.log(foo(100000));"],
+    env: bunEnv,
+    stdout: "pipe",
+    stderr: "pipe",
+  });
+
+  const [stdout, stderr, exitCode] = await Promise.all([
+    new Response(proc.stdout).text(),
+    new Response(proc.stderr).text(),
+    proc.exited,
+  ]);
+
+  expect(stdout.trim()).toBe("0");
+  expect(exitCode).toBe(0);
+});