add a web search agent that extends the current agents' capabilities to real time info search

[HaoZhang615]

Purpose

• ...

Does this introduce a breaking change?

[ ] Yes
[x] No

Pull Request Type

What kind of change does this Pull Request introduce?

[ ] Bugfix
[x] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[ ] Other... Please describe:

How to Deploy

• Get the code

git clone [repo-address]
cd [repo-name]
azd up

Other Information

suggest to add as a feature branch, as we are currently limiting all subscriptions that don't yet have any existing Bing Search resource to create a new one. The Bicep does not provision a Bing Search resource to avoid errors due to this limitation. User deploying this feature branch needs to have an existing Bing Search resource and has access to the API key.