Get Kamelets from remote location

As of today, Karavan only supports specifying a custom Kamelets location as a local file system path. This is inconvenient for teams that want to share and reuse Kamelets, which is their main purpose.

Karavan in VS Code should be able to display and retrieve a catalog of Kamelets from a remote location, such as a Git repository (like `github:apache:camel-kamelets/kamelets`) or a Maven repository (included in a jar dependency like `org.apache.camel.kamelets:camel-kamelets-catalog`).
The repositories may need private access, like credentials and/or private keys.

This way, it will be possible to create Kamelets and share them privately in a company.

Currently, the suggested solution is to clone a git repository in a local filesystem path and configure the Karavan VS Code extension to use this path ([link](https://camel.zulipchat.com/#narrow/stream/322293-camel-karavan/topic/Using.20custom.20kamelet.20jar.20in.20Karavan)).

No implementation files or tests are named. Start by locating the Karavan VS Code extension's handling of the current local Kamelet path and review how its catalog is loaded. Done means displaying and retrieving Kamelets from Git and Maven repositories, including private-access credentials or keys.

Written by the indexing model from the issue text.