NestBot AI Assistant improvement ideas

- do not reply in channels that do not have the ai assistant enabled
- instead of "Thinking" add 👀 reaction to the post that is going to have a reply soon
- ** bold formatting doesn't work
- it shouldn't send everyone to https://owasp.org/contact for more information
- some messages like

> Hey all! I’ve been using OSS forever, and ever since I got into programming, started making small contributions here and there to projects that helped me. Excited to get more involved in this space by learning from everyone here, and contribute where I can. Feels great to join such a welcoming place! :smile:

need to be answered with just a welcome message instead of `Please ask questions related to OWASP.`

- `give me the list of all OWASP flagship projects` reply returns 5 projects only