Split features into codex-features crate (#15253)

- Split the feature system into a new `codex-features` crate.
- Cut `codex-core` and workspace consumers over to the new config and
warning APIs.

Co-authored-by: Ahmed Ibrahim <219906144+aibrahim-oai@users.noreply.github.com>
Co-authored-by: Codex <noreply@openai.com>

codex-rs/tui_app_server/src/app.rs

@@ -68,13 +68,13 @@ use codex_core::config::edit::ConfigEditsBuilder;
 use codex_core::config::types::ApprovalsReviewer;
 use codex_core::config::types::ModelAvailabilityNuxConfig;
 use codex_core::config_loader::ConfigLayerStackOrdering;
-use codex_core::features::Feature;
 use codex_core::message_history;
 use codex_core::models_manager::collaboration_mode_presets::CollaborationModesConfig;
 use codex_core::models_manager::model_presets::HIDE_GPT_5_1_CODEX_MAX_MIGRATION_PROMPT_CONFIG;
 use codex_core::models_manager::model_presets::HIDE_GPT5_1_MIGRATION_PROMPT_CONFIG;
 #[cfg(target_os = "windows")]
 use codex_core::windows_sandbox::WindowsSandboxLevelExt;
+use codex_features::Feature;
 use codex_otel::SessionTelemetry;
 use codex_protocol::ThreadId;
 use codex_protocol::approvals::ExecApprovalRequestEvent;

codex-rs/tui_app_server/src/app_event.rs

@@ -25,7 +25,7 @@ use crate::bottom_pane::StatusLineItem;
 use crate::history_cell::HistoryCell;
 
 use codex_core::config::types::ApprovalsReviewer;
-use codex_core::features::Feature;
+use codex_features::Feature;
 use codex_protocol::config_types::CollaborationModeMask;
 use codex_protocol::config_types::Personality;
 use codex_protocol::config_types::ServiceTier;

codex-rs/tui_app_server/src/bottom_pane/approval_overlay.rs

@@ -16,7 +16,7 @@ use crate::key_hint::KeyBinding;
 use crate::render::highlight::highlight_bash_to_lines;
 use crate::render::renderable::ColumnRenderable;
 use crate::render::renderable::Renderable;
-use codex_core::features::Features;
+use codex_features::Features;
 use codex_protocol::ThreadId;
 use codex_protocol::mcp::RequestId;
 use codex_protocol::models::MacOsAutomationPermission;

codex-rs/tui_app_server/src/bottom_pane/experimental_features_view.rs

@@ -19,7 +19,7 @@ use crate::render::renderable::ColumnRenderable;
 use crate::render::renderable::Renderable;
 use crate::style::user_message_style;
 
-use codex_core::features::Feature;
+use codex_features::Feature;
 
 use super::CancellationEvent;
 use super::bottom_pane_view::BottomPaneView;

codex-rs/tui_app_server/src/bottom_pane/mod.rs

@@ -27,9 +27,9 @@ use crate::render::renderable::Renderable;
 use crate::render::renderable::RenderableItem;
 use crate::tui::FrameRequester;
 use bottom_pane_view::BottomPaneView;
-use codex_core::features::Features;
 use codex_core::plugins::PluginCapabilitySummary;
 use codex_core::skills::model::SkillMetadata;
+use codex_features::Features;
 use codex_file_search::FileMatch;
 use codex_protocol::request_user_input::RequestUserInputEvent;
 use codex_protocol::user_input::TextElement;

codex-rs/tui_app_server/src/chatwidget.rs

@@ -87,8 +87,6 @@ use codex_core::config::types::ApprovalsReviewer;
 use codex_core::config::types::Notifications;
 use codex_core::config::types::WindowsSandboxModeToml;
 use codex_core::config_loader::ConfigLayerStackOrdering;
-use codex_core::features::FEATURES;
-use codex_core::features::Feature;
 use codex_core::find_thread_name_by_id;
 use codex_core::git_info::current_branch_name;
 use codex_core::git_info::get_git_repo_root;
@@ -98,6 +96,8 @@ use codex_core::project_doc::DEFAULT_PROJECT_DOC_FILENAME;
 use codex_core::skills::model::SkillMetadata;
 #[cfg(target_os = "windows")]
 use codex_core::windows_sandbox::WindowsSandboxLevelExt;
+use codex_features::FEATURES;
+use codex_features::Feature;
 use codex_otel::RuntimeMetricsSummary;
 use codex_otel::SessionTelemetry;
 use codex_protocol::ThreadId;

codex-rs/tui_app_server/src/chatwidget/tests.rs

@@ -57,10 +57,10 @@ use codex_core::config_loader::ConfigLayerStack;
 use codex_core::config_loader::ConfigRequirements;
 use codex_core::config_loader::ConfigRequirementsToml;
 use codex_core::config_loader::RequirementSource;
-use codex_core::features::FEATURES;
-use codex_core::features::Feature;
 use codex_core::models_manager::collaboration_mode_presets::CollaborationModesConfig;
 use codex_core::skills::model::SkillMetadata;
+use codex_features::FEATURES;
+use codex_features::Feature;
 use codex_otel::RuntimeMetricsSummary;
 use codex_otel::SessionTelemetry;
 use codex_protocol::ThreadId;

codex-rs/tui_app_server/src/lib.rs

@@ -1594,7 +1594,7 @@ mod tests {
     use codex_core::config::ConfigBuilder;
     use codex_core::config::ConfigOverrides;
     use codex_core::config::ProjectConfig;
-    use codex_core::features::Feature;
+    use codex_features::Feature;
     use codex_protocol::protocol::AskForApproval;
     use codex_protocol::protocol::RolloutItem;
     use codex_protocol::protocol::RolloutLine;

codex-rs/tui_app_server/src/tooltips.rs

@@ -1,4 +1,4 @@
-use codex_core::features::FEATURES;
+use codex_features::FEATURES;
 use codex_protocol::account::PlanType;
 use lazy_static::lazy_static;
 use rand::Rng;