docs: Adding VoyageAI to 'integrations/text_embedding/' dropdown (#28817)

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**Description:** 
Adding VoyageAI's text_embedding to 'integrations/text_embedding/'


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`docs/docs/integrations` directory.


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baskaryan, efriis, eyurtsev, ccurme, vbarda, hwchase17.

docs/src/theme/EmbeddingTabs.js

@@ -25,6 +25,8 @@ export default function EmbeddingTabs(props) {
       hideNomic,
       nvidiaParams,
       hideNvidia,
+      voyageaiParams,
+      hideVoyageai,
       fakeEmbeddingParams,
       hideFakeEmbedding,
       customVarName,
@@ -42,6 +44,7 @@ export default function EmbeddingTabs(props) {
     const mistralParamsOrDefault = mistralParams ?? `model="mistral-embed"`;
     const nomicsParamsOrDefault = nomicParams ?? `model="nomic-embed-text-v1.5"`;
     const nvidiaParamsOrDefault = nvidiaParams ?? `model="NV-Embed-QA"`;
+    const voyageaiParamsOrDefault = voyageaiParams ?? `model="voyage-3"`;
     const fakeEmbeddingParamsOrDefault = fakeEmbeddingParams ?? `size=4096`;
 
     const embeddingVarName = customVarName ?? "embeddings";
@@ -137,6 +140,15 @@ export default function EmbeddingTabs(props) {
         default: false,
         shouldHide: hideNvidia,
       },
+      {
+        value: "Voyage AI",
+        label: "Voyage AI",
+        text: `from langchain-voyageai import VoyageAIEmbeddings\n\n${embeddingVarName} = VoyageAIEmbeddings(${voyageaiParamsOrDefault})`,
+        apiKeyName: "VOYAGE_API_KEY",
+        packageName: "langchain-voyageai",
+        default: false,
+        shouldHide: hideVoyageai,
+      },
       {
         value: "Fake",
         label: "Fake",