* Unify embeddings paths
Our code has two embeddings paths for legacy reasons:
- The capi api based one that only supports text3small. This is used everywhere except `#codebase`
- The new github embeddings endpoint based. This one supports additional embedding types and options. However it is currently only used in `#codebase`
This change switches everything to use the new github embeddings endpoint instead
* Fix static deps in tests
* use enum for model
* add small proxy endpoint and use when needed
* extend endpoint to reduce duplication and imply dependance
* use experiment service
* rename small -> short
* fix model name
* fix type
* separate endpoint impls for upcoming header changes
* remove extra spaces
* Update baseline
* Full update
* Update
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Co-authored-by: Vritant Bhardwaj <vrtoku@gmail.com>
Co-authored-by: Vritant Bhardwaj <vrbhardw@microsoft.com>