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/status/rate_limits.rs

@@ -0,0 +1,235 @@
+use crate::chatwidget::get_limits_duration;
+
+use super::helpers::format_reset_timestamp;
+use chrono::DateTime;
+use chrono::Duration as ChronoDuration;
+use chrono::Local;
+use chrono::Utc;
+use codex_core::protocol::CreditsSnapshot as CoreCreditsSnapshot;
+use codex_core::protocol::RateLimitSnapshot;
+use codex_core::protocol::RateLimitWindow;
+
+const STATUS_LIMIT_BAR_SEGMENTS: usize = 20;
+const STATUS_LIMIT_BAR_FILLED: &str = "█";
+const STATUS_LIMIT_BAR_EMPTY: &str = "░";
+
+#[derive(Debug, Clone)]
+pub(crate) struct StatusRateLimitRow {
+    pub label: String,
+    pub value: StatusRateLimitValue,
+}
+
+#[derive(Debug, Clone)]
+pub(crate) enum StatusRateLimitValue {
+    Window {
+        percent_used: f64,
+        resets_at: Option<String>,
+    },
+    Text(String),
+}
+
+#[derive(Debug, Clone)]
+pub(crate) enum StatusRateLimitData {
+    Available(Vec<StatusRateLimitRow>),
+    Stale(Vec<StatusRateLimitRow>),
+    Missing,
+}
+
+pub(crate) const RATE_LIMIT_STALE_THRESHOLD_MINUTES: i64 = 15;
+
+#[derive(Debug, Clone)]
+pub(crate) struct RateLimitWindowDisplay {
+    pub used_percent: f64,
+    pub resets_at: Option<String>,
+    pub window_minutes: Option<i64>,
+}
+
+impl RateLimitWindowDisplay {
+    fn from_window(window: &RateLimitWindow, captured_at: DateTime<Local>) -> Self {
+        let resets_at = window
+            .resets_at
+            .and_then(|seconds| DateTime::<Utc>::from_timestamp(seconds, 0))
+            .map(|dt| dt.with_timezone(&Local))
+            .map(|dt| format_reset_timestamp(dt, captured_at));
+
+        Self {
+            used_percent: window.used_percent,
+            resets_at,
+            window_minutes: window.window_minutes,
+        }
+    }
+}
+
+#[derive(Debug, Clone)]
+pub(crate) struct RateLimitSnapshotDisplay {
+    pub captured_at: DateTime<Local>,
+    pub primary: Option<RateLimitWindowDisplay>,
+    pub secondary: Option<RateLimitWindowDisplay>,
+    pub credits: Option<CreditsSnapshotDisplay>,
+}
+
+#[derive(Debug, Clone)]
+pub(crate) struct CreditsSnapshotDisplay {
+    pub has_credits: bool,
+    pub unlimited: bool,
+    pub balance: Option<String>,
+}
+
+pub(crate) fn rate_limit_snapshot_display(
+    snapshot: &RateLimitSnapshot,
+    captured_at: DateTime<Local>,
+) -> RateLimitSnapshotDisplay {
+    RateLimitSnapshotDisplay {
+        captured_at,
+        primary: snapshot
+            .primary
+            .as_ref()
+            .map(|window| RateLimitWindowDisplay::from_window(window, captured_at)),
+        secondary: snapshot
+            .secondary
+            .as_ref()
+            .map(|window| RateLimitWindowDisplay::from_window(window, captured_at)),
+        credits: snapshot.credits.as_ref().map(CreditsSnapshotDisplay::from),
+    }
+}
+
+impl From<&CoreCreditsSnapshot> for CreditsSnapshotDisplay {
+    fn from(value: &CoreCreditsSnapshot) -> Self {
+        Self {
+            has_credits: value.has_credits,
+            unlimited: value.unlimited,
+            balance: value.balance.clone(),
+        }
+    }
+}
+
+pub(crate) fn compose_rate_limit_data(
+    snapshot: Option<&RateLimitSnapshotDisplay>,
+    now: DateTime<Local>,
+) -> StatusRateLimitData {
+    match snapshot {
+        Some(snapshot) => {
+            let mut rows = Vec::with_capacity(3);
+
+            if let Some(primary) = snapshot.primary.as_ref() {
+                let label: String = primary
+                    .window_minutes
+                    .map(get_limits_duration)
+                    .unwrap_or_else(|| "5h".to_string());
+                let label = capitalize_first(&label);
+                rows.push(StatusRateLimitRow {
+                    label: format!("{label} limit"),
+                    value: StatusRateLimitValue::Window {
+                        percent_used: primary.used_percent,
+                        resets_at: primary.resets_at.clone(),
+                    },
+                });
+            }
+
+            if let Some(secondary) = snapshot.secondary.as_ref() {
+                let label: String = secondary
+                    .window_minutes
+                    .map(get_limits_duration)
+                    .unwrap_or_else(|| "weekly".to_string());
+                let label = capitalize_first(&label);
+                rows.push(StatusRateLimitRow {
+                    label: format!("{label} limit"),
+                    value: StatusRateLimitValue::Window {
+                        percent_used: secondary.used_percent,
+                        resets_at: secondary.resets_at.clone(),
+                    },
+                });
+            }
+
+            if let Some(credits) = snapshot.credits.as_ref()
+                && let Some(row) = credit_status_row(credits)
+            {
+                rows.push(row);
+            }
+
+            let is_stale = now.signed_duration_since(snapshot.captured_at)
+                > ChronoDuration::minutes(RATE_LIMIT_STALE_THRESHOLD_MINUTES);
+
+            if rows.is_empty() {
+                StatusRateLimitData::Available(vec![])
+            } else if is_stale {
+                StatusRateLimitData::Stale(rows)
+            } else {
+                StatusRateLimitData::Available(rows)
+            }
+        }
+        None => StatusRateLimitData::Missing,
+    }
+}
+
+pub(crate) fn render_status_limit_progress_bar(percent_remaining: f64) -> String {
+    let ratio = (percent_remaining / 100.0).clamp(0.0, 1.0);
+    let filled = (ratio * STATUS_LIMIT_BAR_SEGMENTS as f64).round() as usize;
+    let filled = filled.min(STATUS_LIMIT_BAR_SEGMENTS);
+    let empty = STATUS_LIMIT_BAR_SEGMENTS.saturating_sub(filled);
+    format!(
+        "[{}{}]",
+        STATUS_LIMIT_BAR_FILLED.repeat(filled),
+        STATUS_LIMIT_BAR_EMPTY.repeat(empty)
+    )
+}
+
+pub(crate) fn format_status_limit_summary(percent_remaining: f64) -> String {
+    format!("{percent_remaining:.0}% left")
+}
+
+/// Builds a single `StatusRateLimitRow` for credits when the snapshot indicates
+/// that the account has credit tracking enabled. When credits are unlimited we
+/// show that fact explicitly; otherwise we render the rounded balance in
+/// credits. Accounts with credits = 0 skip this section entirely.
+fn credit_status_row(credits: &CreditsSnapshotDisplay) -> Option<StatusRateLimitRow> {
+    if !credits.has_credits {
+        return None;
+    }
+    if credits.unlimited {
+        return Some(StatusRateLimitRow {
+            label: "Credits".to_string(),
+            value: StatusRateLimitValue::Text("Unlimited".to_string()),
+        });
+    }
+    let balance = credits.balance.as_ref()?;
+    let display_balance = format_credit_balance(balance)?;
+    Some(StatusRateLimitRow {
+        label: "Credits".to_string(),
+        value: StatusRateLimitValue::Text(format!("{display_balance} credits")),
+    })
+}
+
+fn format_credit_balance(raw: &str) -> Option<String> {
+    let trimmed = raw.trim();
+    if trimmed.is_empty() {
+        return None;
+    }
+
+    if let Ok(int_value) = trimmed.parse::<i64>()
+        && int_value > 0
+    {
+        return Some(int_value.to_string());
+    }
+
+    if let Ok(value) = trimmed.parse::<f64>()
+        && value > 0.0
+    {
+        let rounded = value.round() as i64;
+        return Some(rounded.to_string());
+    }
+
+    None
+}
+
+fn capitalize_first(label: &str) -> String {
+    let mut chars = label.chars();
+    match chars.next() {
+        Some(first) => {
+            let mut capitalized = first.to_uppercase().collect::<String>();
+            capitalized.push_str(chars.as_str());
+            capitalized
+        }
+        None => String::new(),
+    }
+}