Enable plain clicks on transcript links and style bare URLs (#46884)

## Why

Transcript links required a modified click to open, and bare URLs lacked the visual styling of explicit Markdown links.

## What changed

- Open links on release after an unmodified, stationary left click. Cancel activation after dragging, scrolling, or releasing elsewhere so text selection remains usable.
- Apply Markdown link styling to bare URLs while preserving surrounding prose, existing emphasis, Unicode, and table wrapping.

## Testing

Add gesture tests for bare and Markdown links at narrow and wide widths, drag and scroll cancellation, and existing modified-click behavior. Add styling tests and snapshots covering punctuation, emphasis, tabs, Unicode, and wrapped table URLs.

GitOrigin-RevId: 23d12c901932d7e3586d841e5a0ece00e422fccd

codex-rs/tui/src/markdown_render/snapshots/codex_tui__markdown_render__web_links__tests__bare_urls_are_styled_without_coloring_surrounding_prose.snap

@@ -0,0 +1,6 @@
+---
+source: tui/src/markdown_render/web_links_tests.rs
+assertion_line: 37
+expression: text
+---
+Text::from(Line::from_iter([Span::from("界 ("), Span::from("https://example.com/a").fg(Color::Reset).underlined(), Span::from("); "), Span::from("https://example.com/b").fg(Color::Reset).underlined(), Span::from("! "), Span::from("https://example.com/c").fg(Color::Reset).bold().underlined()]))

codex-rs/tui/src/markdown_render/snapshots/codex_tui__markdown_render__web_links__tests__bare_urls_keep_link_style_when_wrapped_in_tables.snap

@@ -0,0 +1,20 @@
+---
+source: tui/src/markdown_render/web_links_tests.rs
+assertion_line: 63
+expression: text
+---
+Text::from_iter([
+    Line::from_iter([
+        Span::from(" "),
+        Span::from("Resource"),
+    ]).fg(Color::Rgb(249, 226, 175)).bold(),
+    Line::from(Span::from("━━━━━━━━━━━━━━━━━━━━").dim()),
+    Line::from_iter([
+        Span::from(" "),
+        Span::from("https://").fg(Color::Reset).underlined(),
+    ]),
+    Line::from_iter([
+        Span::from(" "),
+        Span::from("example.com/docs").fg(Color::Reset).underlined(),
+    ]),
+])

codex-rs/tui/src/markdown_render/web_links.rs

@@ -1,4 +1,4 @@
-//! Presentation policy for web-link destinations in semantic Markdown output.
+//! Styling and destination visibility for web links in semantic Markdown output.
 //!
 //! Terminal identity is a conservative heuristic, not end-to-end capability negotiation. Unknown
 //! terminals and multiplexers retain the destination so a label never hides the only usable URL.
@@ -9,7 +9,50 @@ use codex_terminal_detection::terminal_info;
 use std::io::IsTerminal;
 use std::sync::LazyLock;
 
+use ratatui::style::Style;
+use ratatui::text::Line;
+use ratatui::text::Span;
+use unicode_segmentation::UnicodeSegmentation;
+
+use crate::terminal_hyperlinks::HyperlinkLine;
+use crate::terminal_hyperlinks::annotate_web_urls_in_line;
 use crate::terminal_hyperlinks::web_destination;
+use crate::width::display_width;
+
+/// Give detected URLs the same affordance as explicit Markdown links, preserving surrounding text.
+pub(super) fn style_bare_web_urls(span: Span<'static>, link_style: Style) -> HyperlinkLine {
+    let mut line = annotate_web_urls_in_line(Line::from(span));
+    if line.hyperlinks.is_empty() {
+        return line;
+    }
+    let mut spans: Vec<Span<'static>> = Vec::new();
+    let mut links = line.hyperlinks.iter().peekable();
+    let mut column = 0;
+    let span = &line.line.spans[0];
+    for grapheme in span.content.graphemes(/*is_extended*/ true) {
+        while links.peek().is_some_and(|link| link.columns.end <= column) {
+            links.next();
+        }
+        let style = if links
+            .peek()
+            .is_some_and(|link| link.columns.contains(&column))
+        {
+            span.style.patch(link_style)
+        } else {
+            span.style
+        };
+        if let Some(last) = spans.last_mut()
+            && last.style == style
+        {
+            last.content.to_mut().push_str(grapheme);
+        } else {
+            spans.push(Span::styled(grapheme.to_owned(), style));
+        }
+        column += display_width(grapheme);
+    }
+    line.line.spans = spans;
+    line
+}
 
 #[derive(Clone, Copy, PartialEq, Eq)]
 enum WebLinkDisplay {

codex-rs/tui/src/markdown_render/web_links_tests.rs

@@ -10,11 +10,62 @@ use codex_terminal_detection::TerminalInfo;
 use codex_terminal_detection::TerminalName;
 use insta::assert_debug_snapshot;
 use pretty_assertions::assert_eq;
+use ratatui::style::Style;
 use ratatui::style::Stylize;
 use ratatui::text::Line;
 use ratatui::text::Text;
 use std::collections::BTreeSet;
 
+#[test]
+fn bare_urls_are_styled_without_coloring_surrounding_prose() {
+    let text = Text::from(visible_lines(render(
+        "界 (https://example.com/a); https://example.com/b! **https://example.com/c**",
+        /*width*/ 100,
+        WebLinkDisplay::LabelOnly,
+    )));
+    assert_eq!(
+        text,
+        Text::from(Line::from(vec![
+            "界 (".into(),
+            "https://example.com/a".fg(accent_color()).underlined(),
+            "); ".into(),
+            "https://example.com/b".fg(accent_color()).underlined(),
+            "! ".into(),
+            "https://example.com/c"
+                .bold()
+                .fg(accent_color())
+                .underlined(),
+        ])),
+    );
+    assert_debug_snapshot!(text);
+}
+
+#[test]
+fn bare_url_styling_preserves_tabs_and_unicode() {
+    let line = super::style_bare_web_urls(
+        "界\t(https://example.com).".bold(),
+        Style::new().fg(accent_color()).underlined(),
+    );
+    assert_eq!(
+        line.line,
+        Line::from(vec![
+            "界\t(".bold(),
+            "https://example.com".bold().fg(accent_color()).underlined(),
+            ").".bold(),
+        ]),
+    );
+}
+
+#[test]
+fn bare_urls_keep_link_style_when_wrapped_in_tables() {
+    let text = Text::from(visible_lines(render(
+        "| Resource |\n| --- |\n| https://example.com/docs |",
+        /*width*/ 20,
+        WebLinkDisplay::LabelOnly,
+    )));
+    assert_debug_snapshot!(text);
+}
+
 fn terminal(name: TerminalName) -> TerminalInfo {
     TerminalInfo {
         name,