Documentation on how to manually install the extension

[milost]

It would be great if you could provide some documentation or a short example/tutorial on how to manually install the VectorChord extension in an existing Postgres instance.

[VoVAllen]

You can use the zip or deb package in our release https://github.com/tensorchord/VectorChord/releases/tag/0.2.0.

The detailed process can be found in https://docs.vectorchord.ai/vectorchord/getting-started/installation.html#from-zip-package.

[gaocegege]

We should document it, I think.