Update README.md with Foundry buttons, RAG Deep Dive link

[pamelafox]

Purpose

This PR builds on the PR from @amynic, but situates the Foundry buttons in the Getting Help section, to make it clear what kinds of questions developers should take to the Foundry.
This PR also updates the resources links to point at the latest video series, RAG Deep Dive. I thought I did that in a different PR, but I don't know where it went to.

Does this introduce a breaking change?

When developers merge from main and run the server, azd up, or azd deploy, will this produce an error?
If you're not sure, try it out on an old environment.

[ ] Yes
[X] No

Does this require changes to learn.microsoft.com docs?

This repository is referenced by this tutorial
which includes deployment, settings and usage instructions. If text or screenshot need to change in the tutorial,
check the box below and notify the tutorial author. A Microsoft employee can do this for you if you're an external contributor.

[ ] Yes
[X] No

Type of change

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

Code quality checklist

See CONTRIBUTING.md for more details.

N/A

[Copilot]

Pull Request Overview

This PR updates the README to surface the new RAG Deep Dive video series link and adds Azure AI Foundry community badges under the Getting help section.

• Added a “📺 Video: RAG Deep Dive Series” resource link
• Inserted Azure AI Foundry Discord and Forum badges in Getting help

Comments suppressed due to low confidence (2)

README.md:282

• [nitpick] Consider adding a brief description of what the RAG Deep Dive Series covers (e.g., recordings of deep dive sessions) so readers understand the resource’s value at a glance.

- [📺 Video: RAG Deep Dive Series](https://techcommunity.microsoft.com/blog/azuredevcommunityblog/rag-deep-dive-watch-all-the-recordings/4383171)

README.md:292

• [nitpick] To keep the list formatting consistent under 'Getting help', consider prefixing this line (and the following badges) with a list bullet or indenting them to align with the other list items in this section.

For general questions about developing AI solutions on Azure,