[Feature] using vertex groups/attributes as pins

Motivation

the current pinning system is quite limiting, it for one a little bit tedious (and a little buggy, i will report a bug in a second), and most importantly, it doesn't work with vertex groups/custom attributes that can be influenced by other things like modifiers or geonodes.

Proposal

unsure if it'll take time to implement, but it would be great to replace the current pinning system with group based "pin" fields (groups as in the same way for the simulated objects, where you make as much groups as you want, and you set your objects as input, in this case, the vertex groups/attributes will be the inputs)

Alternatives Considered

No response

Additional Context

No response

Contribution Agreement

• I confirm that any code, patches, scripts, attachments, or other copyrightable material I include in this issue may be used, reproduced, modified, and distributed by this project under the Apache License 2.0 or as otherwise described in CONTRIBUTING.md.
• This is a feature request from the community (please provide a reference below).

Community Reference

No response

No files, tests, or entry points are named. Start by locating the current pinning system and the existing group-based inputs for simulated objects; done should mean vertex groups or custom attributes can drive pins, including values affected by modifiers or geometry nodes.