feat(tui2): copy tui crate and normalize snapshots (#7833)

Introduce a full codex-tui source snapshot under the new codex-tui2
crate so viewport work can be replayed in isolation.

This change copies the entire codex-rs/tui/src tree into
codex-rs/tui2/src in one atomic step, rather than piecemeal, to keep
future diffs vs the original viewport bookmark easy to reason about.

The goal is for codex-tui2 to render identically to the existing TUI
behind the `features.tui2` flag while we gradually port the
viewport/history commits from the joshka/viewport bookmark onto this
forked tree.

While on this baseline change, we also ran the codex-tui2 snapshot test
suite and accepted all insta snapshots for the new crate, so the
snapshot files now use the codex-tui2 naming scheme and encode the
unmodified legacy TUI behavior. This keeps later viewport commits
focused on intentional behavior changes (and their snapshots) rather
than on mechanical snapshot renames.

codex-rs/tui2/src/app_event.rs

@@ -0,0 +1,185 @@
+use std::path::PathBuf;
+
+use codex_common::approval_presets::ApprovalPreset;
+use codex_core::protocol::ConversationPathResponseEvent;
+use codex_core::protocol::Event;
+use codex_core::protocol::RateLimitSnapshot;
+use codex_file_search::FileMatch;
+use codex_protocol::openai_models::ModelPreset;
+
+use crate::bottom_pane::ApprovalRequest;
+use crate::history_cell::HistoryCell;
+
+use codex_core::protocol::AskForApproval;
+use codex_core::protocol::SandboxPolicy;
+use codex_protocol::openai_models::ReasoningEffort;
+
+#[allow(clippy::large_enum_variant)]
+#[derive(Debug)]
+pub(crate) enum AppEvent {
+    CodexEvent(Event),
+
+    /// Start a new session.
+    NewSession,
+
+    /// Open the resume picker inside the running TUI session.
+    OpenResumePicker,
+
+    /// Request to exit the application gracefully.
+    ExitRequest,
+
+    /// Forward an `Op` to the Agent. Using an `AppEvent` for this avoids
+    /// bubbling channels through layers of widgets.
+    CodexOp(codex_core::protocol::Op),
+
+    /// Kick off an asynchronous file search for the given query (text after
+    /// the `@`). Previous searches may be cancelled by the app layer so there
+    /// is at most one in-flight search.
+    StartFileSearch(String),
+
+    /// Result of a completed asynchronous file search. The `query` echoes the
+    /// original search term so the UI can decide whether the results are
+    /// still relevant.
+    FileSearchResult {
+        query: String,
+        matches: Vec<FileMatch>,
+    },
+
+    /// Result of refreshing rate limits
+    RateLimitSnapshotFetched(RateLimitSnapshot),
+
+    /// Result of computing a `/diff` command.
+    DiffResult(String),
+
+    InsertHistoryCell(Box<dyn HistoryCell>),
+
+    StartCommitAnimation,
+    StopCommitAnimation,
+    CommitTick,
+
+    /// Update the current reasoning effort in the running app and widget.
+    UpdateReasoningEffort(Option<ReasoningEffort>),
+
+    /// Update the current model slug in the running app and widget.
+    UpdateModel(String),
+
+    /// Persist the selected model and reasoning effort to the appropriate config.
+    PersistModelSelection {
+        model: String,
+        effort: Option<ReasoningEffort>,
+    },
+
+    /// Open the reasoning selection popup after picking a model.
+    OpenReasoningPopup {
+        model: ModelPreset,
+    },
+
+    /// Open the full model picker (non-auto models).
+    OpenAllModelsPopup {
+        models: Vec<ModelPreset>,
+    },
+
+    /// Open the confirmation prompt before enabling full access mode.
+    OpenFullAccessConfirmation {
+        preset: ApprovalPreset,
+    },
+
+    /// Open the Windows world-writable directories warning.
+    /// If `preset` is `Some`, the confirmation will apply the provided
+    /// approval/sandbox configuration on Continue; if `None`, it performs no
+    /// policy change and only acknowledges/dismisses the warning.
+    #[cfg_attr(not(target_os = "windows"), allow(dead_code))]
+    OpenWorldWritableWarningConfirmation {
+        preset: Option<ApprovalPreset>,
+        /// Up to 3 sample world-writable directories to display in the warning.
+        sample_paths: Vec<String>,
+        /// If there are more than `sample_paths`, this carries the remaining count.
+        extra_count: usize,
+        /// True when the scan failed (e.g. ACL query error) and protections could not be verified.
+        failed_scan: bool,
+    },
+
+    /// Prompt to enable the Windows sandbox feature before using Agent mode.
+    #[cfg_attr(not(target_os = "windows"), allow(dead_code))]
+    OpenWindowsSandboxEnablePrompt {
+        preset: ApprovalPreset,
+    },
+
+    /// Enable the Windows sandbox feature and switch to Agent mode.
+    #[cfg_attr(not(target_os = "windows"), allow(dead_code))]
+    EnableWindowsSandboxForAgentMode {
+        preset: ApprovalPreset,
+    },
+
+    /// Update the current approval policy in the running app and widget.
+    UpdateAskForApprovalPolicy(AskForApproval),
+
+    /// Update the current sandbox policy in the running app and widget.
+    UpdateSandboxPolicy(SandboxPolicy),
+
+    /// Update whether the full access warning prompt has been acknowledged.
+    UpdateFullAccessWarningAcknowledged(bool),
+
+    /// Update whether the world-writable directories warning has been acknowledged.
+    #[cfg_attr(not(target_os = "windows"), allow(dead_code))]
+    UpdateWorldWritableWarningAcknowledged(bool),
+
+    /// Update whether the rate limit switch prompt has been acknowledged for the session.
+    UpdateRateLimitSwitchPromptHidden(bool),
+
+    /// Persist the acknowledgement flag for the full access warning prompt.
+    PersistFullAccessWarningAcknowledged,
+
+    /// Persist the acknowledgement flag for the world-writable directories warning.
+    #[cfg_attr(not(target_os = "windows"), allow(dead_code))]
+    PersistWorldWritableWarningAcknowledged,
+
+    /// Persist the acknowledgement flag for the rate limit switch prompt.
+    PersistRateLimitSwitchPromptHidden,
+
+    /// Persist the acknowledgement flag for the model migration prompt.
+    PersistModelMigrationPromptAcknowledged {
+        migration_config: String,
+    },
+
+    /// Skip the next world-writable scan (one-shot) after a user-confirmed continue.
+    #[cfg_attr(not(target_os = "windows"), allow(dead_code))]
+    SkipNextWorldWritableScan,
+
+    /// Re-open the approval presets popup.
+    OpenApprovalsPopup,
+
+    /// Forwarded conversation history snapshot from the current conversation.
+    ConversationHistory(ConversationPathResponseEvent),
+
+    /// Open the branch picker option from the review popup.
+    OpenReviewBranchPicker(PathBuf),
+
+    /// Open the commit picker option from the review popup.
+    OpenReviewCommitPicker(PathBuf),
+
+    /// Open the custom prompt option from the review popup.
+    OpenReviewCustomPrompt,
+
+    /// Open the approval popup.
+    FullScreenApprovalRequest(ApprovalRequest),
+
+    /// Open the feedback note entry overlay after the user selects a category.
+    OpenFeedbackNote {
+        category: FeedbackCategory,
+        include_logs: bool,
+    },
+
+    /// Open the upload consent popup for feedback after selecting a category.
+    OpenFeedbackConsent {
+        category: FeedbackCategory,
+    },
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub(crate) enum FeedbackCategory {
+    BadResult,
+    GoodResult,
+    Bug,
+    Other,
+}