Move config schema helper out of codex-core package

Keep package-level codex-core checks focused on the library by moving the schema writer binary into its own workspace package and updating the just recipe to call that package directly.

Co-authored-by: Codex <noreply@openai.com>

codex-rs/write-config-schema/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+edition.workspace = true
+license.workspace = true
+name = "codex-write-config-schema"
+version.workspace = true
+
+[lints]
+workspace = true
+
+[dependencies]
+anyhow = { workspace = true }
+clap = { workspace = true, features = ["derive"] }
+codex-core = { workspace = true }

codex-rs/write-config-schema/src/main.rs

@@ -0,0 +1,23 @@
+use std::path::PathBuf;
+
+use anyhow::Result;
+use clap::Parser;
+
+/// Generate the JSON Schema for `config.toml` and write it to `config.schema.json`.
+#[derive(Parser)]
+#[command(name = "codex-write-config-schema")]
+struct Args {
+    #[arg(short, long, value_name = "PATH")]
+    out: Option<PathBuf>,
+}
+
+fn main() -> Result<()> {
+    let args = Args::parse();
+    let out_path = args.out.unwrap_or_else(|| {
+        PathBuf::from(env!("CARGO_MANIFEST_DIR"))
+            .join("../core")
+            .join("config.schema.json")
+    });
+    codex_core::config::schema::write_config_schema(&out_path)?;
+    Ok(())
+}