Move git utilities into a dedicated crate (#15564)

- create `codex-git-utils` and move the shared git helpers into it with
file moves preserved for diff readability
- move the `GitInfo` helpers out of `core` so stacked rollout work can
depend on the shared crate without carrying its own git info module

---------

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/chatwidget.rs

@@ -89,9 +89,6 @@ use codex_core::config::types::Notifications;
 use codex_core::config::types::WindowsSandboxModeToml;
 use codex_core::config_loader::ConfigLayerStackOrdering;
 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;
-use codex_core::git_info::local_git_branches;
 use codex_core::plugins::PluginsManager;
 use codex_core::project_doc::DEFAULT_PROJECT_DOC_FILENAME;
 use codex_core::skills::model::SkillMetadata;
@@ -99,6 +96,12 @@ use codex_core::skills::model::SkillMetadata;
 use codex_core::windows_sandbox::WindowsSandboxLevelExt;
 use codex_features::FEATURES;
 use codex_features::Feature;
+#[cfg(test)]
+use codex_git_utils::CommitLogEntry;
+use codex_git_utils::current_branch_name;
+use codex_git_utils::get_git_repo_root;
+use codex_git_utils::local_git_branches;
+use codex_git_utils::recent_commits;
 use codex_otel::RuntimeMetricsSummary;
 use codex_otel::SessionTelemetry;
 use codex_protocol::ThreadId;
@@ -10414,7 +10417,7 @@ impl ChatWidget {
     }
 
     pub(crate) async fn show_review_commit_picker(&mut self, cwd: &Path) {
-        let commits = codex_core::git_info::recent_commits(cwd, /*limit*/ 100).await;
+        let commits = recent_commits(cwd, /*limit*/ 100).await;
 
         let mut items: Vec<SelectionItem> = Vec::with_capacity(commits.len());
         for entry in commits {
@@ -10796,7 +10799,7 @@ fn hook_event_label(event_name: codex_protocol::protocol::HookEventName) -> &'st
 #[cfg(test)]
 pub(crate) fn show_review_commit_picker_with_entries(
     chat: &mut ChatWidget,
-    entries: Vec<codex_core::git_info::CommitLogEntry>,
+    entries: Vec<CommitLogEntry>,
 ) {
     let mut items: Vec<SelectionItem> = Vec::with_capacity(entries.len());
     for entry in entries {

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

@@ -74,6 +74,7 @@ use codex_core::plugins::OPENAI_CURATED_MARKETPLACE_NAME;
 use codex_core::skills::model::SkillMetadata;
 use codex_features::FEATURES;
 use codex_features::Feature;
+use codex_git_utils::CommitLogEntry;
 use codex_otel::RuntimeMetricsSummary;
 use codex_otel::SessionTelemetry;
 use codex_protocol::ThreadId;
@@ -7322,12 +7323,12 @@ async fn review_commit_picker_shows_subjects_without_timestamps() {
 
     // Show commit picker with synthetic entries.
     let entries = vec![
-        codex_core::git_info::CommitLogEntry {
+        CommitLogEntry {
             sha: "1111111deadbeef".to_string(),
             timestamp: 0,
             subject: "Add new feature X".to_string(),
         },
-        codex_core::git_info::CommitLogEntry {
+        CommitLogEntry {
             sha: "2222222cafebabe".to_string(),
             timestamp: 0,
             subject: "Fix bug Y".to_string(),

codex-rs/tui_app_server/src/diff_render.rs

@@ -92,7 +92,7 @@ use crate::terminal_palette::default_bg;
 use crate::terminal_palette::indexed_color;
 use crate::terminal_palette::rgb_color;
 use crate::terminal_palette::stdout_color_level;
-use codex_core::git_info::get_git_repo_root;
+use codex_git_utils::get_git_repo_root;
 use codex_protocol::protocol::FileChange;
 use codex_terminal_detection::TerminalName;
 use codex_terminal_detection::terminal_info;

codex-rs/tui_app_server/src/onboarding/trust_directory.rs

@@ -1,7 +1,7 @@
 use std::path::PathBuf;
 
 use codex_core::config::set_project_trust_level;
-use codex_core::git_info::resolve_root_git_project_for_trust;
+use codex_git_utils::resolve_root_git_project_for_trust;
 use codex_protocol::config_types::TrustLevel;
 use crossterm::event::KeyCode;
 use crossterm::event::KeyEvent;