Remove the legacy TUI split (#15922)

This is the part 1 of 2 PRs that will delete the `tui` /
`tui_app_server` split. This part simply deletes the existing `tui`
directory and marks the `tui_app_server` feature flag as removed. I left
the `tui_app_server` feature flag in place for now so its presence
doesn't result in an error. It is simply ignored.

Part 2 will rename the `tui_app_server` directory `tui`. I did this as
two parts to reduce visible code churn.

codex-rs/tui/src/status/format.rs

@@ -1,147 +0,0 @@
-use ratatui::prelude::*;
-use ratatui::style::Stylize;
-use std::collections::BTreeSet;
-use unicode_width::UnicodeWidthChar;
-use unicode_width::UnicodeWidthStr;
-
-#[derive(Debug, Clone)]
-pub(crate) struct FieldFormatter {
-    indent: &'static str,
-    label_width: usize,
-    value_offset: usize,
-    value_indent: String,
-}
-
-impl FieldFormatter {
-    pub(crate) const INDENT: &'static str = " ";
-
-    pub(crate) fn from_labels<S>(labels: impl IntoIterator<Item = S>) -> Self
-    where
-        S: AsRef<str>,
-    {
-        let label_width = labels
-            .into_iter()
-            .map(|label| UnicodeWidthStr::width(label.as_ref()))
-            .max()
-            .unwrap_or(0);
-        let indent_width = UnicodeWidthStr::width(Self::INDENT);
-        let value_offset = indent_width + label_width + 1 + 3;
-
-        Self {
-            indent: Self::INDENT,
-            label_width,
-            value_offset,
-            value_indent: " ".repeat(value_offset),
-        }
-    }
-
-    pub(crate) fn line(
-        &self,
-        label: &'static str,
-        value_spans: Vec<Span<'static>>,
-    ) -> Line<'static> {
-        Line::from(self.full_spans(label, value_spans))
-    }
-
-    pub(crate) fn continuation(&self, mut spans: Vec<Span<'static>>) -> Line<'static> {
-        let mut all_spans = Vec::with_capacity(spans.len() + 1);
-        all_spans.push(Span::from(self.value_indent.clone()).dim());
-        all_spans.append(&mut spans);
-        Line::from(all_spans)
-    }
-
-    pub(crate) fn value_width(&self, available_inner_width: usize) -> usize {
-        available_inner_width.saturating_sub(self.value_offset)
-    }
-
-    pub(crate) fn full_spans(
-        &self,
-        label: &str,
-        mut value_spans: Vec<Span<'static>>,
-    ) -> Vec<Span<'static>> {
-        let mut spans = Vec::with_capacity(value_spans.len() + 1);
-        spans.push(self.label_span(label));
-        spans.append(&mut value_spans);
-        spans
-    }
-
-    fn label_span(&self, label: &str) -> Span<'static> {
-        let mut buf = String::with_capacity(self.value_offset);
-        buf.push_str(self.indent);
-
-        buf.push_str(label);
-        buf.push(':');
-
-        let label_width = UnicodeWidthStr::width(label);
-        let padding = 3 + self.label_width.saturating_sub(label_width);
-        for _ in 0..padding {
-            buf.push(' ');
-        }
-
-        Span::from(buf).dim()
-    }
-}
-
-pub(crate) fn push_label(labels: &mut Vec<String>, seen: &mut BTreeSet<String>, label: &str) {
-    if seen.contains(label) {
-        return;
-    }
-
-    let owned = label.to_string();
-    seen.insert(owned.clone());
-    labels.push(owned);
-}
-
-pub(crate) fn line_display_width(line: &Line<'static>) -> usize {
-    line.iter()
-        .map(|span| UnicodeWidthStr::width(span.content.as_ref()))
-        .sum()
-}
-
-pub(crate) fn truncate_line_to_width(line: Line<'static>, max_width: usize) -> Line<'static> {
-    if max_width == 0 {
-        return Line::from(Vec::<Span<'static>>::new());
-    }
-
-    let mut used = 0usize;
-    let mut spans_out: Vec<Span<'static>> = Vec::new();
-
-    for span in line.spans {
-        let text = span.content.into_owned();
-        let style = span.style;
-        let span_width = UnicodeWidthStr::width(text.as_str());
-
-        if span_width == 0 {
-            spans_out.push(Span::styled(text, style));
-            continue;
-        }
-
-        if used >= max_width {
-            break;
-        }
-
-        if used + span_width <= max_width {
-            used += span_width;
-            spans_out.push(Span::styled(text, style));
-            continue;
-        }
-
-        let mut truncated = String::new();
-        for ch in text.chars() {
-            let ch_width = UnicodeWidthChar::width(ch).unwrap_or(0);
-            if used + ch_width > max_width {
-                break;
-            }
-            truncated.push(ch);
-            used += ch_width;
-        }
-
-        if !truncated.is_empty() {
-            spans_out.push(Span::styled(truncated, style));
-        }
-
-        break;
-    }
-
-    Line::from(spans_out)
-}