Make embedding generation go through inference (#606)

This PR does the following:
1) adds the ability to generate embeddings in all supported inference
providers.
2) Moves all the memory providers to use the inference API and improved
the memory tests to setup the inference stack correctly and use the
embedding models

This is a merge from #589 and #598

llama_stack/providers/remote/memory/weaviate/weaviate.py

@@ -12,10 +12,11 @@ import weaviate
 import weaviate.classes as wvc
 from numpy.typing import NDArray
 from weaviate.classes.init import Auth
+from weaviate.classes.query import Filter
 
 from llama_stack.apis.memory import *  # noqa: F403
 from llama_stack.distribution.request_headers import NeedsRequestProviderData
-from llama_stack.providers.datatypes import MemoryBanksProtocolPrivate
+from llama_stack.providers.datatypes import Api, MemoryBanksProtocolPrivate
 from llama_stack.providers.utils.memory.vector_store import (
     BankWithIndex,
     EmbeddingIndex,
@@ -80,12 +81,21 @@ class WeaviateIndex(EmbeddingIndex):
 
         return QueryDocumentsResponse(chunks=chunks, scores=scores)
 
+    async def delete(self, chunk_ids: List[str]) -> None:
+        collection = self.client.collections.get(self.collection_name)
+        collection.data.delete_many(
+            where=Filter.by_property("id").contains_any(chunk_ids)
+        )
+
 
 class WeaviateMemoryAdapter(
-    Memory, NeedsRequestProviderData, MemoryBanksProtocolPrivate
+    Memory,
+    NeedsRequestProviderData,
+    MemoryBanksProtocolPrivate,
 ):
-    def __init__(self, config: WeaviateConfig) -> None:
+    def __init__(self, config: WeaviateConfig, inference_api: Api.inference) -> None:
         self.config = config
+        self.inference_api = inference_api
         self.client_cache = {}
         self.cache = {}
 
@@ -117,7 +127,7 @@ class WeaviateMemoryAdapter(
         memory_bank: MemoryBank,
     ) -> None:
         assert (
-            memory_bank.memory_bank_type == MemoryBankType.vector
+            memory_bank.memory_bank_type == MemoryBankType.vector.value
         ), f"Only vector banks are supported {memory_bank.memory_bank_type}"
 
         client = self._get_client()
@@ -135,11 +145,11 @@ class WeaviateMemoryAdapter(
                 ],
             )
 
-        index = BankWithIndex(
-            bank=memory_bank,
-            index=WeaviateIndex(client=client, collection_name=memory_bank.identifier),
+        self.cache[memory_bank.identifier] = BankWithIndex(
+            memory_bank,
+            WeaviateIndex(client=client, collection_name=memory_bank.identifier),
+            self.inference_api,
         )
-        self.cache[memory_bank.identifier] = index
 
     async def _get_and_cache_bank_index(self, bank_id: str) -> Optional[BankWithIndex]:
         if bank_id in self.cache:
@@ -156,6 +166,7 @@ class WeaviateMemoryAdapter(
         index = BankWithIndex(
             bank=bank,
             index=WeaviateIndex(client=client, collection_name=bank_id),
+            inference_api=self.inference_api,
         )
         self.cache[bank_id] = index
         return index