doc: add table of contents, tc/triager lists to readme

[mertcanaltin]

I have created a table and I think this place can provide convenience In addition, I created areas introducing cooperation, technical committee, triagers.

added space for Code of Conduct

(unfortunately, some e-mails are missing, I couldn't find them :( I could not add some people, I can add the missing participants 🙏)

@UlisesGascon @wesleytodd @CBID2

[mertcanaltin]

I added the missing triagers based on this list: https://github.com/orgs/expressjs/teams/triagers

[jonchurch]

@UlisesGascon did you want to wait for anymore team changes? Otherwise, squash and merge when ready

[mertcanaltin]

@jonchurch thank you for support 🙏🚀

[jonchurch]

related https://github.com/expressjs/discussions/issues/230

[mertcanaltin]

thank you @jonchurch ı accepted updates