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/model/editlog.rs

@@ -0,0 +1,64 @@
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct EditLogEntry {
+    pub ts: i64,
+    pub tool: String,
+    pub path: String,
+    pub reason: String,
+    pub content_sha256: String,
+    pub bytes_delta: i64,
+    pub origin: String,
+    pub session_id: String,
+}
+
+#[derive(Debug, Clone)]
+pub struct EditLog {
+    pub entries: Vec<EditLogEntry>,
+    pub path: std::path::PathBuf,
+}
+
+impl EditLog {
+    pub fn new(session_dir: &std::path::Path) -> Self {
+        EditLog {
+            entries: Vec::new(),
+            path: session_dir.join("edits.jsonl"),
+        }
+    }
+
+    pub fn append(&mut self, entry: EditLogEntry) -> std::io::Result<()> {
+        let line = serde_json::to_string(&entry)? + "\n";
+        let parent = self.path.parent().unwrap();
+        std::fs::create_dir_all(parent)?;
+        let mut file = std::fs::OpenOptions::new()
+            .create(true)
+            .append(true)
+            .open(&self.path)?;
+        use std::io::Write;
+        file.write_all(line.as_bytes())?;
+        self.entries.push(entry);
+        Ok(())
+    }
+
+    pub fn load(path: &std::path::Path) -> std::io::Result<Self> {
+        let content = std::fs::read_to_string(path)?;
+        let entries: Vec<EditLogEntry> = content
+            .lines()
+            .filter_map(|l| serde_json::from_str(l).ok())
+            .collect();
+        Ok(EditLog {
+            entries,
+            path: path.to_path_buf(),
+        })
+    }
+
+    pub fn recent(&self, n: usize) -> &[EditLogEntry] {
+        let len = self.entries.len();
+        let start = len.saturating_sub(n);
+        &self.entries[start..]
+    }
+
+    pub fn len(&self) -> usize {
+        self.entries.len()
+    }
+}