feat: projects (revamped documents section)

[tjbck]

3521 #3231 #2044 #3110 #3464 #1096

• [ ] Refactor Collection handling -> Rename it to project
• [ ] Deprecate current tags in favour of project groupping
• [ ] Each project should be able to handle multiple files (save all embeddings to same collection)
• [ ] Team admins (#2924) should be able to create/manage projects within the team workspace
• [ ] Should be team-agnostic and should allow inter-team project use case
• [ ] Project notes (#3231)
• [ ] Provide clear guidance on API usage
  • Upload file via Files API
  • Process and link file to project(s) using file id
  • Chat with Files using project id(s) in chat completion payload

[joelmnz]

In addition to my suggestion in #3231 , have seen what Claude has done with their "agent workspaces" (a space/doc an agent can read & write to), that is a great idea, what if we could get our agents/chats to have read-write memory/notes. I have seen the concept of "memory" in Open WebUI but haven't found docs or how to use it. Could that be incorporated, maybe as a separate ticket but considered here.

If this is done already or in some other way please let me know.

[jannikstdl]

Very exited!