chore: reduce tokio features to rt+macros

CLAUDE.md

@@ -257,7 +257,6 @@ Tracks child processes that have open ports. When a parent session dies but the
 - **Rust** (2021 edition)
 - **ratatui** + **crossterm** for TUI
 - **serde** + **serde_json** for JSON/JSONL parsing
-- **tokio** — included but currently sync I/O; summary generation uses `std::thread::spawn`
 - **chrono** for timestamp formatting
 - **dirs** for home directory resolution
 - **Polling intervals** (staggered to avoid freezes):

Cargo.toml

@@ -15,7 +15,6 @@ authors = ["Tae Hwan Jung <nlkey2022@gmail.com>"]
 [dependencies]
 ratatui = "0.29"
 crossterm = "0.28"
-tokio = { version = "1", features = ["full"] }
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 dirs = "6"

src/collector/codex.rs

@@ -450,11 +450,9 @@ fn parse_codex_jsonl(path: &Path) -> Option<CodexJSONLResult> {
                             result.context_window = cw;
                         }
                     }
-                    Some("user_message") => {
-                        if result.initial_prompt.is_empty() {
-                            if let Some(msg) = payload["message"].as_str() {
-                                result.initial_prompt = msg.chars().take(120).collect();
-                            }
+                    Some("user_message") if result.initial_prompt.is_empty() => {
+                        if let Some(msg) = payload["message"].as_str() {
+                            result.initial_prompt = msg.chars().take(120).collect();
                         }
                     }
                     Some("token_count") => {