feat: add ability for background tasks and local storage

[LiuChangFreeman]

- compact source code files, all convert to typescript

Now all source codes are converted to typescript. We don't use .js for source code anymore.

- add chrome api for background tasks and local storage

Now in src/pages/Background/index.ts, we can do tasks which should be done every several minutes. Such as checking for updates or getting daily notice. In src/utils/utils.ts, I make a wrapper for chrome.storage.local.set()/get(), and we can store meta data in user's local storage by calling await easily. Here is an example:

export async function test(){
  const key="test",value=100;
  await chrome_set(key,value);
  const result=await chrome_get(key);
  console.log(result);
  // and you will get: {"test":100}
}

test();// call it somewhere else

[heming6666]

Great job! Thanks @LiuChangFreeman .

/approve