Native Embedder model selection (incl: Multilingual support) (#3835)

* WIP on embedder selection
TODO: apply splitting and query prefixes (if applicable)

* wip on upsert

* Support base model
support nomic-text-embed-v1
support multilingual-e5-small
Add prefixing for both embedding and query for RAG tasks
Add chunking prefix to all vector dbs to apply prefix when possible
Show dropdown and auto-pull on new selection

* norm translations

* move supported models to constants
handle null seelction or invalid selection on dropdown
update comments

* dev

* patch text splitter maximums for now

* normalize translations

* add tests for splitter functionality

* normalize

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Co-authored-by: shatfield4 <seanhatfield5@gmail.com>

server/storage/models/.gitignore

@@ -9,4 +9,5 @@ gemini
 togetherAi
 tesseract
 ppio
-context-windows/*
+context-windows/*
+MintplexLabs