Runtime init reload after panic

Some runtimes crash with panics because they assume the environment will self recover, because that's Lambda's behavior when you deploy a function. It'd be very useful if the emulator would initialize the runtime again if the runtime crashed with a panic.

Otherwise, people have to restart the emulator, and it's not very obvious that you have to do that by looking at the logs either.

先定位 emulator 的 runtime 初始化與 panic 處理路徑，接著追蹤發生 crash 的 runtime 如何在日誌中回報。完成的標準是：panic 會讓 runtime 重新初始化，而不需要重新啟動 emulator，且相關測試涵蓋此行為。

由索引模型根據 Issue 內容生成。