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/settings.rs

@@ -0,0 +1,78 @@
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+#[derive(Default)]
+pub enum InternetMode {
+    #[default]
+    Off,
+    ReadOnly,
+    Full,
+}
+
+impl InternetMode {
+    pub fn can_fetch(&self) -> bool {
+        matches!(self, InternetMode::Full)
+    }
+
+    pub fn can_download(&self) -> bool {
+        matches!(self, InternetMode::Full)
+    }
+
+    pub fn can_search(&self) -> bool {
+        matches!(self, InternetMode::Full)
+    }
+}
+
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct Settings {
+    pub internet_mode: InternetMode,
+    pub provider: String,
+    pub model: String,
+    pub api_key: Option<String>,
+    pub max_tokens: u32,
+    pub temperature: f32,
+    pub review_enabled: bool,
+    pub review_max_lessons_per_run: usize,
+    pub adaptive_review_max_skip: u32,
+    pub workflow_max_concurrency: usize,
+    pub session_archive_enabled: bool,
+}
+
+impl Default for Settings {
+    fn default() -> Self {
+        Settings {
+            internet_mode: InternetMode::Off,
+            provider: "openrouter".to_string(),
+            model: "anthropic/claude-opus-4-8".to_string(),
+            api_key: None,
+            max_tokens: 8192,
+            temperature: 0.7,
+            review_enabled: true,
+            review_max_lessons_per_run: 5,
+            adaptive_review_max_skip: 3,
+            workflow_max_concurrency: 5,
+            session_archive_enabled: true,
+        }
+    }
+}
+
+impl Settings {
+    pub fn load() -> Self {
+        let store = super::store::Store::new();
+        let path = store.base_dir.join("settings.json");
+        std::fs::read_to_string(path)
+            .ok()
+            .and_then(|s| serde_json::from_str(&s).ok())
+            .unwrap_or_default()
+    }
+
+    pub fn save(&self) -> std::io::Result<()> {
+        let store = super::store::Store::new();
+        std::fs::create_dir_all(&store.base_dir)?;
+        let path = store.base_dir.join("settings.json");
+        let s = serde_json::to_string_pretty(self)?;
+        std::fs::write(path, s)?;
+        Ok(())
+    }
+}