Add huggingface dedicated provider support

[Yuqi-Du]

since provider huggingfaceDedicated does not require model, modelName field in createCollectionCommand will be changed as allow null. Other providers still need model specified, so validations move down to createCollectionCommandResolver.

For huggingFace dedicated, the endpoint we use is:

• url: https://{endpointName}.{regionName}.{cloudName}.endpoints.huggingface.cloud/embeddings
• Note, this is an openAI compatible endpoint
• https://huggingface.github.io/text-embeddings-inference/#/Text%20Embeddings%20Inference/embed

We do not require modelName, but dimension is still needed, and will error out is not provided.
Also, parameters: endpointName, regionName, cloudName are needed to compute the url.

Fixes #1145

Checklist

• Changes manually tested
• Automated Tests added/updated
• Documentation added/updated
• CLA Signed: DataStax CLA

[tatu-at-datastax]

Looks good, but I was wondering if the 2 new checks (for not requiring model name; for requiring dimensions) could be based only on embedding provider configuration and not require hard-coded checks for newly added provider.

[tatu-at-datastax]

LGTM, added minor comments.

[a-effort]

@Yuqi-Du , here is content for the form fields for Hugging Face — Dedicated create collection:

Label: User access token
Placeholder: Select user access token

Label: Embedding model
Placeholder: Select embedding model
Helper text under form field: Model to use to generate embeddings

Label: Endpoint name
Placeholder: Add endpoint name
Helper text under form field: Add the first part of the dedicated endpoint URL

Label: Region name
Placeholder: Add region name
Helper text under form field: Add the second part of the dedicated endpoint URL

Label: Cloud provider the dedicated endpoint is deployed to
Placeholder: Add cloud name
Helper text under form field: Add the third part of the dedicated endpoint URL

Label: Dimensions
Placeholder: Add a number between 2 and 3072
Helper text under form field: Vector length in your dataset (between 2 and 3072)