Reduce js_repl Node version requirement to 22.22.0 (#12857)

## Summary

Lower the `js_repl` minimum Node version from `24.13.1` to `22.22.0`.

This updates the enforced minimum in `codex-rs/node-version.txt` and the
corresponding user-facing `/experimental` description for the JavaScript
REPL feature.

## Rationale

The previous `24.13.1` floor was stricter than necessary for `js_repl`.
I validated the REPL kernel behavior under Node `22.22.0` still works.

## Why `22.22.0`

`22.22.0` is a current, widely packaged Node 22 release across common
developer environments and distros, including Homebrew `node@22`, Fedora
`nodejs22`, Arch `nodejs-lts-jod`, and Debian testing. That makes it a
better exact floor than guessing at an older `22.x` patch we have not
validated.

`22.x` is also a maintenance branch that will be supported through April
2027, where the previous maintenance branch of `20.x` is only supported
through April of this year.

## Changes

- Update `codex-rs/node-version.txt` from `24.13.1` to `22.22.0`
- Update the `/experimental` JavaScript REPL description to say
`Requires Node >= v22.22.0 installed.`

codex-rs/core/src/features.rs

@@ -463,7 +463,7 @@ pub const FEATURES: &[FeatureSpec] = &[
         key: "js_repl",
         stage: Stage::Experimental {
             name: "JavaScript REPL",
-            menu_description: "Enable a persistent Node-backed JavaScript REPL for interactive website debugging and other inline JavaScript execution capabilities. Requires Node >= v24.13.1 installed.",
+            menu_description: "Enable a persistent Node-backed JavaScript REPL for interactive website debugging and other inline JavaScript execution capabilities. Requires Node >= v22.22.0 installed.",
             announcement: "NEW: JavaScript REPL is now available in /experimental. Enable it, then start a new chat or restart Codex to use it.",
         },
         default_enabled: false,

codex-rs/node-version.txt

@@ -1 +1 @@
-24.13.1
+22.22.0