Move worker duty into socket io server.

Pros:

• No unnecessary Redis stream
  • The current worker is based on a polling mechanism, which leads to inefficiency
  • Now we don't have to recreate the ydoc in different places several times
• Reactive stream processing
  • Now Redis stream operations for room happen only on update instead of worker polling
  • No pending task and stream entry accumulation

Cons:

• Pressure on socket io server would be higher
• Due to caching, expected memory usage would be higher

Others:

• Implementing heavy caching in the server to avoid unnecessary operation as much as possible
  • Authentication result is now cached for 1m
  • Server now maintains a copy of ydoc