Add session persistence and browser functionality

- Implement `StorageManager` for saving, loading, and managing sessions.
- Introduce platform-specific session directories for persistence.
- Add session browser UI for listing, loading, and deleting saved sessions.
- Enable AI-generated descriptions for session summaries.
- Update configurations to support storage settings and description generation.
- Extend README and tests to document and validate new functionality.

crates/owlen-core/src/session.rs

@@ -218,4 +218,88 @@ impl SessionController {
     pub fn clear(&mut self) {
         self.conversation.clear();
     }
+
+    /// Generate a short AI description for the current conversation
+    pub async fn generate_conversation_description(&self) -> Result<String> {
+        let conv = self.conversation.active();
+
+        // If conversation is empty or very short, return a simple description
+        if conv.messages.is_empty() {
+            return Ok("Empty conversation".to_string());
+        }
+
+        if conv.messages.len() == 1 {
+            let first_msg = &conv.messages[0];
+            let preview = first_msg.content.chars().take(50).collect::<String>();
+            return Ok(format!("{}{}", preview, if first_msg.content.len() > 50 { "..." } else { "" }));
+        }
+
+        // Build a summary prompt from the first few and last few messages
+        let mut summary_messages = Vec::new();
+
+        // Add system message to guide the description
+        summary_messages.push(crate::types::Message::system(
+            "Summarize this conversation in 1-2 short sentences (max 100 characters). \
+             Focus on the main topic or question being discussed. Be concise and descriptive.".to_string()
+        ));
+
+        // Include first message
+        if let Some(first) = conv.messages.first() {
+            summary_messages.push(first.clone());
+        }
+
+        // Include a middle message if conversation is long enough
+        if conv.messages.len() > 4 {
+            if let Some(mid) = conv.messages.get(conv.messages.len() / 2) {
+                summary_messages.push(mid.clone());
+            }
+        }
+
+        // Include last message
+        if let Some(last) = conv.messages.last() {
+            if conv.messages.len() > 1 {
+                summary_messages.push(last.clone());
+            }
+        }
+
+        // Create a summarization request
+        let request = crate::types::ChatRequest {
+            model: conv.model.clone(),
+            messages: summary_messages,
+            parameters: crate::types::ChatParameters {
+                temperature: Some(0.3), // Lower temperature for more focused summaries
+                max_tokens: Some(50),   // Keep it short
+                stream: false,
+                extra: std::collections::HashMap::new(),
+            },
+        };
+
+        // Get the summary from the provider
+        match self.provider.chat(request).await {
+            Ok(response) => {
+                let description = response.message.content.trim().to_string();
+
+                // If description is empty, use fallback
+                if description.is_empty() {
+                    let first_msg = &conv.messages[0];
+                    let preview = first_msg.content.chars().take(50).collect::<String>();
+                    return Ok(format!("{}{}", preview, if first_msg.content.len() > 50 { "..." } else { "" }));
+                }
+
+                // Truncate if too long
+                let truncated = if description.len() > 100 {
+                    format!("{}...", description.chars().take(97).collect::<String>())
+                } else {
+                    description
+                };
+                Ok(truncated)
+            }
+            Err(_e) => {
+                // Fallback to simple description if AI generation fails
+                let first_msg = &conv.messages[0];
+                let preview = first_msg.content.chars().take(50).collect::<String>();
+                Ok(format!("{}{}", preview, if first_msg.content.len() > 50 { "..." } else { "" }))
+            }
+        }
+    }
 }