Update and restructure Qdrant integration docs

[alistairmatthews]

The existing Qdrant integration document is comprehensive but difficult for beginners. This PR is intended to keep the comprehensive information but make it easier for those who want to get going quickly. I've used Copilot to propagate changes from the new PostgreSQL documents to the Qdrant ones.

This PR:

• Splits the large integration doc into two: Hosting and Client.
• Adds a getting started short tutorial.
• Adds a Properties of the Qdrant resources section to the client reference docs. This describes what configuration values are injected by the WithReference() method.