fix: always load version from package.json at runtime

codex-cli/src/version.ts

@@ -0,0 +1,8 @@
+// Note that "../package.json" is marked external in build.mjs. This ensures
+// that the contents of package.json will always be read at runtime, which is
+// preferable so we do not have to make a temporary change to package.json in
+// the source tree to update the version number in the code.
+import pkg from "../package.json" with { type: "json" };
+
+// Read the version directly from package.json.
+export const CLI_VERSION: string = (pkg as { version: string }).version;