have a "standard" format for embeddings integrations

right now they are all very different. maybe we include info like

- [ ] description
- [ ] dimensionality
- [ ] max input tokens
- [ ] tokenizer
- [ ] cost
- [ ] languages (english, other?)
- [ ] performance stats? on MTEB/BEIR?
- [ ] decoder 
- [ ] how to get an API Key
- [ ] link to their docs / marketing