Improve transport documentation

[yusefnapora]

Done Criteria

Transports to add:

• QUIC
• WebTransport

Additional improvements:

• Interaction diagrams for dial / listen flow
• Details about switch / swarm & how the dialer works in practice
• Examples of different multiaddrs for various transports

Context

We have a basic concept doc for transports, but there's opportunity to improve on the content and fill in the gap of missing transport documentation.

Notes

See note from recent docs triage.

[p-shahi]

Transport section should mention Quic and WebSockets (later on WebRTC as well.) Setting this as P1 mainly for Quic docs

[salmad3]

Interaction diagrams to be covered in #206, switch is part of #33 & #202, and examples of different multiaddrs added for QUIC and WebTransport when we added content, which we'll follow for other transports that are added (such as WebRTC eventually). Closing this in favor of opening follow up (targeted) issues for the transport documentation to add on new transports or improve on the content.