refactor: websearch into a service

[chuasonglin1995]

Relates to

Remove Tavily from core https://github.com/elizaOS/eliza/issues/2123

Risks

Low. While it touches core, its mainly to remove tavily from core and turn it into a service.

Background

What does this PR do?

Main change that is requested from lalatune

• Remove Tavily from core and convert it into a service.

Other things that I did:

• [Improvement]: Added suppressInitialMessage for webSearch Action. If not the conversation would have two messages
• [Improvement]: Websearch plugin was created in the early ages, so it did not follow the standard that was set. Plugins should be created with folders - /actions, /evaluators etc

Documentation changes needed?

I added some instructions so that others can also use this webSearchService outside of the agents.

Testing

Works well

Discord username

--> song_45935

[tcm390]

I just tested it, and it works well! 😊

[wtfsayo]

lfg