feat(tui): Add confirmation prompt for enabling full access approvals (#4980)

## Summary
Adds a confirmation screen when a user attempts to select Full Access
via the `/approvals` flow in the TUI.

If the user selects the remember option, the preference is persisted to
config.toml as `full_access_warning_acknowledged`, so they will not be
prompted again.


## Testing
- [x] Adds snapshot test coverage for the approvals flow and the
confirmation flow
<img width="865" height="187" alt="Screenshot 2025-10-08 at 6 04 59 PM"
src="https://github.com/user-attachments/assets/fd1dac62-28b0-4835-ba91-5da6dc5ec4c4"
/>



------
https://chatgpt.com/codex/tasks/task_i_68e6c5c458088322a28efa3207058180

---------

Co-authored-by: Fouad Matin <169186268+fouad-openai@users.noreply.github.com>
Co-authored-by: Fouad Matin <fouad@openai.com>

codex-rs/tui/src/app.rs

@@ -18,6 +18,7 @@ use codex_core::AuthManager;
 use codex_core::ConversationManager;
 use codex_core::config::Config;
 use codex_core::config::persist_model_selection;
+use codex_core::config::set_hide_full_access_warning;
 use codex_core::model_family::find_family_for_model;
 use codex_core::protocol::SessionSource;
 use codex_core::protocol::TokenUsage;
@@ -334,6 +335,9 @@ impl App {
             AppEvent::OpenReasoningPopup { model, presets } => {
                 self.chat_widget.open_reasoning_popup(model, presets);
             }
+            AppEvent::OpenFullAccessConfirmation { preset } => {
+                self.chat_widget.open_full_access_confirmation(preset);
+            }
             AppEvent::PersistModelSelection { model, effort } => {
                 let profile = self.active_profile.as_deref();
                 match persist_model_selection(&self.config.codex_home, profile, &model, effort)
@@ -379,6 +383,23 @@ impl App {
             AppEvent::UpdateSandboxPolicy(policy) => {
                 self.chat_widget.set_sandbox_policy(policy);
             }
+            AppEvent::UpdateFullAccessWarningAcknowledged(ack) => {
+                self.chat_widget.set_full_access_warning_acknowledged(ack);
+            }
+            AppEvent::PersistFullAccessWarningAcknowledged => {
+                if let Err(err) = set_hide_full_access_warning(&self.config.codex_home, true) {
+                    tracing::error!(
+                        error = %err,
+                        "failed to persist full access warning acknowledgement"
+                    );
+                    self.chat_widget.add_error_message(format!(
+                        "Failed to save full access confirmation preference: {err}"
+                    ));
+                }
+            }
+            AppEvent::OpenApprovalsPopup => {
+                self.chat_widget.open_approvals_popup();
+            }
             AppEvent::OpenReviewBranchPicker(cwd) => {
                 self.chat_widget.show_review_branch_picker(&cwd).await;
             }