V45.39: fix SERVER OFFLINE lau + UI load cham - engine ghi port file (engine_port.txt), UI bootstrap doc port engine cua chinh no (get_engine_port) + timeout/retry 60s, health poll self-heal reload, khong taskkill /IM daw_engine (giet engine instance khac), /api/v1/plugins/available chay scan trong threadpool (khong chan event loop -> /health het timeout)

src-tauri/src/lib.rs

@@ -294,7 +294,8 @@ pub fn run() {
             transport_control,
             set_fx_chain,
             restart_bridge_with_sample_rate,
-            dbg_log
+            dbg_log,
+            get_engine_port
         ])
         .setup(|app| {
             // V10 (FIX_DRAG_DROP_WINDOWS): disable Tauri's built-in drag-drop
@@ -741,7 +742,12 @@ pub fn run() {
                     // taskkill chi nhan MOT /IM moi lan goi — goi rieng cho tung
                     // process, khong gop /IM ... /IM (truoc day chi cai dau chay,
                     // fx_vst_bridge/plugin_host song sot thanh orphan).
-                    for im in ["daw_engine.exe", "daw_vst_bridge.exe",
+                    // KHONG taskkill /IM daw_engine.exe: image name dung chung moi
+                    // instance — se giet ca engine cua app KHAC dang chay (2 app
+                    // cung luc: dong 1 cai → app kia mat server → SERVER OFFLINE).
+                    // Engine cua chinh minh da duoc kill_process_tree o tren; con
+                    // sot (crash/khong parent) tu thoat nho watchdog SF_PARENT_PID.
+                    for im in ["daw_vst_bridge.exe",
                                "fx_vst_bridge.exe", "plugin_host.exe"] {
                         let _ = std::process::Command::new("taskkill")
                             .args(["/IM", im, "/T", "/F"])
@@ -904,6 +910,22 @@ fn bridge_status(app: AppHandle) -> Result<BridgeStatus, String> {
 /// V28: JS timing diagnostics — append `{unix_ms} {tag} {extra}` to
 /// %APPDATA%/SonicForgeDAW/logs/dbg.log (create dirs as needed). Fire-and-forget
 /// từ app.jsx (_dbgLog) để định vị delay Play/Stop không cần devtools.
+/// Port engine đã chọn (desktop_engine.py ghi %APPDATA%/SonicForgeDAW/
+/// engine_port.txt ngay sau _pick_port). UI bootstrap ưu tiên dùng port này
+/// để kết nối ĐÚNG engine của chính mình; -1 khi chưa có (engine đang khởi
+/// động) → bootstrap retry/fallback quét 8000-8010.
+#[tauri::command]
+fn get_engine_port() -> i32 {
+    let appdata = std::env::var("APPDATA").unwrap_or_else(|_| ".".into());
+    let path = std::path::Path::new(&appdata)
+        .join("SonicForgeDAW")
+        .join("engine_port.txt");
+    std::fs::read_to_string(path)
+        .ok()
+        .and_then(|s| s.trim().parse::<i32>().ok())
+        .unwrap_or(-1)
+}
+
 #[tauri::command]
 fn dbg_log(tag: String, extra: String) -> Result<(), String> {
     let Some(appdata) = std::env::var("APPDATA").ok() else { return Ok(()) };