refactor: improve code readability and consistency across multiple files

apps/interfaces/tui/src/state.rs

@@ -788,7 +788,7 @@ pub fn count_tokens(text: &str) -> usize {
         return bpe.encode_with_special_tokens(text).len();
     }
     // Fallback: ~4 chars per token
-    (text.len() + 3) / 4
+    text.len().div_ceil(4)
 }
 
 // ---------------------------------------------------------------------------

apps/interfaces/tui/src/turn.rs

@@ -3,7 +3,7 @@
 //! Flow: push user message → spawn OS thread → loop: call blocking LLM
 //! client → execute tool calls → push TurnEvents → repeat until done.
 
-use std::path::PathBuf;
+use std::path::{Path, PathBuf};
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::{Arc, Mutex};
 use std::collections::VecDeque;
@@ -53,7 +53,7 @@ pub fn spawn_agent_turn(state: &mut AppStateRest, text: String) {
 /// The core agent turn — LLM call → tool execution → repeat.
 fn run_turn(
     messages: &mut Vec<ChatMessage>,
-    session_dir: &PathBuf,
+    session_dir: &Path,
     workspace_roots: &[PathBuf],
     turn_events: &Arc<Mutex<VecDeque<TurnEvent>>>,
     in_flight: &Arc<Mutex<bool>>,
@@ -89,7 +89,7 @@ fn run_turn(
     messages.insert(0, sys_msg);
 
     let tool_ctx = ToolCtx::builder()
-        .session_dir(session_dir.clone())
+        .session_dir(session_dir.to_path_buf())
         .workspaces(workspace_roots.to_vec())
         .build();