Implement chat and markdown views, enhance status bar, and add workflow panel

- Added `chat.rs` for rendering chat messages with timestamps and roles.
- Introduced `markdown.rs` for rendering markdown content with styling.
- Created `status.rs` to display the application status bar with session and message counts.
- Developed `workflow.rs` to show the current workflow status, including tool calls and active jobs.
- Established a `theme.rs` for centralized color management across the UI.
- Updated `mod.rs` to include new modules and manage rendering logic.

src/view/markdown.rs

@@ -0,0 +1,143 @@
+use ratatui::style::{Color, Modifier, Style};
+use ratatui::text::Span;
+
+pub fn render_markdown<'a>(text: &'a str, width: u16) -> Vec<Span<'a>> {
+    let mut spans = Vec::new();
+    let parser = pulldown_cmark::Parser::new(text);
+    let mut in_code_block = false;
+
+    for event in parser {
+        match event {
+            pulldown_cmark::Event::Start(tag) => {
+                match tag {
+                    pulldown_cmark::Tag::CodeBlock(_) => {
+                        in_code_block = true;
+                        spans.push(Span::styled(
+                            "```\n",
+                            Style::default().fg(Color::DarkGray),
+                        ));
+                    }
+                    pulldown_cmark::Tag::Heading { level, .. } => {
+                        let color = match level {
+                            pulldown_cmark::HeadingLevel::H1 => Color::LightCyan,
+                            pulldown_cmark::HeadingLevel::H2 => Color::Cyan,
+                            _ => Color::White,
+                        };
+                        let prefix = match level {
+                            pulldown_cmark::HeadingLevel::H1 => "# ",
+                            pulldown_cmark::HeadingLevel::H2 => "## ",
+                            pulldown_cmark::HeadingLevel::H3 => "### ",
+                            _ => "# ",
+                        };
+                        spans.push(Span::styled(
+                            prefix,
+                            Style::default().fg(color).add_modifier(Modifier::BOLD),
+                        ));
+                    }
+                    pulldown_cmark::Tag::Paragraph => {}
+                    pulldown_cmark::Tag::Emphasis => {}
+                    pulldown_cmark::Tag::Strong => {}
+                    pulldown_cmark::Tag::List(_) => {}
+                    pulldown_cmark::Tag::Item => {
+                        spans.push(Span::styled(
+                            "  * ",
+                            Style::default().fg(Color::DarkGray),
+                        ));
+                    }
+                    pulldown_cmark::Tag::Link { dest_url, .. } => {
+                        spans.push(Span::styled(
+                            "[",
+                            Style::default().fg(Color::Cyan),
+                        ));
+                        spans.push(Span::styled(
+                            format!("]({})", dest_url),
+                            Style::default().fg(Color::Blue),
+                        ));
+                    }
+                    pulldown_cmark::Tag::BlockQuote(_) => {
+                        spans.push(Span::styled(
+                            "> ",
+                            Style::default().fg(Color::DarkGray),
+                        ));
+                    }
+                    _ => {}
+                }
+            }
+            pulldown_cmark::Event::End(tag) => {
+                match tag {
+                    pulldown_cmark::TagEnd::CodeBlock => {
+                        in_code_block = false;
+                        spans.push(Span::styled(
+                            "\n```\n",
+                            Style::default().fg(Color::DarkGray),
+                        ));
+                    }
+                    pulldown_cmark::TagEnd::Heading(_) => {
+                        spans.push(Span::raw("\n"));
+                    }
+                    pulldown_cmark::TagEnd::Paragraph => {
+                        spans.push(Span::raw("\n\n"));
+                    }
+                    pulldown_cmark::TagEnd::Emphasis => {}
+                    pulldown_cmark::TagEnd::Strong => {}
+                    pulldown_cmark::TagEnd::List(_) => {}
+                    pulldown_cmark::TagEnd::Item => {
+                        spans.push(Span::raw("\n"));
+                    }
+                    pulldown_cmark::TagEnd::Link => {}
+                    pulldown_cmark::TagEnd::BlockQuote(_) => {
+                        spans.push(Span::raw("\n"));
+                    }
+                    _ => {}
+                }
+            }
+            pulldown_cmark::Event::Text(text) => {
+                let s = text.to_string();
+                if in_code_block {
+                    spans.push(Span::styled(
+                        s,
+                        Style::default().fg(Color::Green),
+                    ));
+                } else {
+                    spans.push(Span::raw(s));
+                }
+            }
+            pulldown_cmark::Event::Code(text) => {
+                spans.push(Span::styled(
+                    format!("`{}`", text),
+                    Style::default().fg(Color::Green),
+                ));
+            }
+            pulldown_cmark::Event::SoftBreak => {
+                spans.push(Span::raw("\n"));
+            }
+            pulldown_cmark::Event::HardBreak => {
+                spans.push(Span::raw("\n"));
+            }
+            _ => {}
+        }
+    }
+
+    if width > 0 {
+        let mut spans_out = Vec::new();
+        let mut line_len = 0;
+        for span in &spans {
+            let s = span.content.clone();
+            let text = s.as_ref();
+            let remaining = text.len();
+            if line_len + remaining > width as usize && line_len > 0 {
+                spans_out.push(Span::raw("\n"));
+                line_len = 0;
+            }
+            spans_out.push(Span::raw(text.to_string()));
+            if !text.contains('\n') {
+                line_len += remaining;
+            } else {
+                line_len = text.split('\n').next_back().unwrap_or("").len();
+            }
+        }
+        spans = spans_out;
+    }
+
+    spans
+}