chore(client): 增加调试日志以导出 NBT stop 结构

用于排查非停站指令（如设置最高速度、新建时刻表区段）的 NBT 结构，
以便后续在代码中精准过滤这些非车站指令。

station_broadcast.lua

@@ -1,6 +1,6 @@
 
 -- 1. Configuration & Constants
-local APP_VERSION_TEXT = "v1.0.51"
+local APP_VERSION_TEXT = "v1.0.52"
 
 local CONFIG = {
     CLOUD_URL = "ws://stabadmin.fse-media.group",
@@ -2626,6 +2626,16 @@ function Main.loop()
                 cleanupTimestampMap(State.announcedAlerts, now, tonumber(CONFIG.ALERT_COOLDOWN_MS) or 300000)
                 
                 for i, stop in ipairs(data.TrainStops) do
+                    -- [DEBUG] Dump first stop to file for inspection
+                    if i == 1 and not State.dumpedStop then
+                        State.dumpedStop = true
+                        local f = fs.open("stop_dump.json", "w")
+                        if f then
+                            f.write(textutils.serializeJSON(stop))
+                            f.close()
+                            Utils.log("DEBUG", "Dumped stop structure to stop_dump.json")
+                        end
+                    end
                     local st = stop.Station
                     if st then
                         local trainName = st.TrainName or "Unknown"