fix: use TOML parser instead of regex for Codex model extraction (#2222) (#2227)

* fix(codex): use TOML parser instead of regex for model extraction

Regex only matched model=... on first line, TOML parser handles
multiline TOML correctly.

Fixes #2222

* fix(stream_check): drop unused regex::Regex import

The previous commit replaced the only Regex usage in stream_check.rs
with toml::Table parsing, leaving `use regex::Regex;` orphaned.
Without this removal, `cargo clippy -- -D warnings` (run in CI)
fails with `unused import: regex::Regex`.

---------

Co-authored-by: Jason <farion1231@gmail.com>

src-tauri/src/services/stream_check.rs

@@ -3,7 +3,6 @@
 //! 使用流式 API 进行快速健康检查，只需接收首个 chunk 即判定成功。
 
 use futures::StreamExt;
-use regex::Regex;
 use reqwest::Client;
 use serde::{Deserialize, Serialize};
 use serde_json::json;
@@ -1412,10 +1411,11 @@ impl StreamCheckService {
             return None;
         }
 
-        let re = Regex::new(r#"^model\s*=\s*["']([^"']+)["']"#).ok()?;
-        re.captures(config_text)
-            .and_then(|caps| caps.get(1))
-            .map(|m| m.as_str().trim().to_string())
+        let table = toml::from_str::<toml::Table>(config_text).ok()?;
+        table
+            .get("model")
+            .and_then(|v| v.as_str())
+            .map(|s| s.trim().to_string())
             .filter(|value| !value.is_empty())
     }