* move agent to langchains_agent
* remove old .env
* remove the old agent folder
* add preliminary version of Agent abstraction
* add preliminary version of the main.py
* merge controlloop and main into a Agent class
* add init
* fix json import
* fix missing arg
* get langchains_agent working after abstraction
* rename `research` to `agenthub`
* rename: rename research to agenthub
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Co-authored-by: huybery <huybery@gmail.com>