[codex] Remove codex-core config type shim (#16529)

## Why

This finishes the config-type move out of `codex-core` by removing the
temporary compatibility shim in `codex_core::config::types`. Callers now
depend on `codex-config` directly, which keeps these config model types
owned by the config crate instead of re-expanding `codex-core` as a
transitive API surface.

## What Changed

- Removed the `codex-rs/core/src/config/types.rs` re-export shim and the
`core::config::ApprovalsReviewer` re-export.
- Updated `codex-core`, `codex-cli`, `codex-tui`, `codex-app-server`,
`codex-mcp-server`, and `codex-linux-sandbox` call sites to import
`codex_config::types` directly.
- Added explicit `codex-config` dependencies to downstream crates that
previously relied on the `codex-core` re-export.
- Regenerated `codex-rs/core/config.schema.json` after updating the
config docs path reference.

codex-rs/core/src/plugins/manager_tests.rs

@@ -1,7 +1,6 @@
 use super::*;
 use crate::config::CONFIG_TOML_FILE;
 use crate::config::ConfigBuilder;
-use crate::config::types::McpServerTransportConfig;
 use crate::config_loader::ConfigLayerEntry;
 use crate::config_loader::ConfigLayerStack;
 use crate::config_loader::ConfigRequirements;
@@ -14,6 +13,7 @@ use crate::plugins::test_support::write_curated_plugin_sha_with as write_curated
 use crate::plugins::test_support::write_file;
 use crate::plugins::test_support::write_openai_curated_marketplace;
 use codex_app_server_protocol::ConfigLayerSource;
+use codex_config::types::McpServerTransportConfig;
 use codex_login::CodexAuth;
 use codex_protocol::protocol::Product;
 use pretty_assertions::assert_eq;