Add ability to bookmark pipelines

We use the asset IDs for direct access links to our assets. But pipeline IDs are generated by KFP (outside our control). So the URLs for the same pipeline on different MLX instances are different, i.e. https://ml-exchange.org/pipelines/00b6accf-be88-7825-6b52-360c07beddef
And if on and the same pipeline gets deleted and re-uploaded, it will have a different ID. This presents a problem when users want to include links to pipelines on MLX in presentations, articles, blog posts, Github issues, etc.

The MLX API should be extended to add something like a `"human_id"` column in the pipeline extension table which will be used for the direct access links. I assume the KFP-generated ID may need to be retained in parallel to launch pipelines and retrieve pipeline run results (@drewbutlerbb4 ?)

FYI @Tomcli @animeshsingh