feat: add lesson export and import functionality

- Implemented `LessonExport` and `LessonImport` actions in the action module.
- Added corresponding command parsing for lesson export and import.
- Created functions to handle lesson export and import in the memory module.
- Updated state management to reflect changes after lesson operations.
- Introduced deferred operations for handling asynchronous tasks in the event loop.
- Enhanced the tool execution context to include graduated checks for file operations.
- Added OAuth support with PKCE for secure authorization flows.
- Implemented a loopback server for handling OAuth redirects.
- Refactored various modules to improve code organization and maintainability.

src/app/runtime/shortsend.rs

@@ -0,0 +1,38 @@
+use crate::dto::chat::message::ChatMessage;
+
+const MAX_WIRE_TOKENS: usize = 8000;
+const MIN_MESSAGES_BEFORE_SHAPE: usize = 20;
+const ENGAGE_HYSTERESIS: usize = 5;
+
+pub fn should_shape(total_messages: usize, prev_shaped: bool) -> bool {
+    if total_messages < MIN_MESSAGES_BEFORE_SHAPE {
+        return false;
+    }
+    let threshold = if prev_shaped {
+        MIN_MESSAGES_BEFORE_SHAPE + ENGAGE_HYSTERESIS
+    } else {
+        MIN_MESSAGES_BEFORE_SHAPE
+    };
+    total_messages >= threshold
+}
+
+pub fn shape_messages(messages: &[ChatMessage], token_count: usize) -> Vec<ChatMessage> {
+    if token_count <= MAX_WIRE_TOKENS || messages.len() < 10 {
+        return messages.to_vec();
+    }
+    let keep_recent = messages
+        .iter()
+        .rev()
+        .take(MAX_WIRE_TOKENS / 200)
+        .cloned()
+        .collect::<Vec<_>>();
+    let mut result = Vec::new();
+    if let Some(first) = messages.first() {
+        result.push(first.clone());
+    }
+    result.push(ChatMessage::system(
+        "[prior conversation compacted]".to_string(),
+    ));
+    result.extend(keep_recent.into_iter().rev());
+    result
+}