[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/tools/handlers/multi_agents_tests.rs

@@ -3,7 +3,6 @@ use crate::ThreadManager;
 use crate::built_in_model_providers;
 use crate::codex::make_session_and_context;
 use crate::config::DEFAULT_AGENT_MAX_DEPTH;
-use crate::config::types::ShellEnvironmentPolicy;
 use crate::function_tool::FunctionCallError;
 use crate::session_prefix::format_subagent_notification_message;
 use crate::state::TaskKind;
@@ -17,6 +16,7 @@ use crate::tools::handlers::multi_agents_v2::SendMessageHandler as SendMessageHa
 use crate::tools::handlers::multi_agents_v2::SpawnAgentHandler as SpawnAgentHandlerV2;
 use crate::tools::handlers::multi_agents_v2::WaitAgentHandler as WaitAgentHandlerV2;
 use crate::turn_diff_tracker::TurnDiffTracker;
+use codex_config::types::ShellEnvironmentPolicy;
 use codex_features::Feature;
 use codex_login::AuthManager;
 use codex_login::CodexAuth;