Java: Add Gemini ChatCompletion and HuggingFace (#6023)

### Motivation and Context

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### Description

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### Contribution Checklist

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- [ ] The code builds clean without any errors or warnings
- [ ] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [ ] All unit tests pass, and I have added new tests where possible
- [ ] I didn't break anyone 😄

---------

Co-authored-by: John Oliver <[email protected]>

java/aiservices/google/pom.xml

@@ -0,0 +1,59 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <parent>
+        <groupId>com.microsoft.semantic-kernel</groupId>
+        <artifactId>semantickernel-parent</artifactId>
+        <version>1.1.6-SNAPSHOT</version>
+        <relativePath>../../pom.xml</relativePath>
+    </parent>
+
+    <artifactId>semantickernel-aiservices-google</artifactId>
+    <name>Semantic Kernel Google Services</name>
+    <description>Google services for Semantic Kernel</description>
+
+    <dependencyManagement>
+        <dependencies>
+            <dependency>
+                <groupId>com.google.cloud</groupId>
+                <artifactId>libraries-bom</artifactId>
+                <version>26.37.0</version>
+                <type>pom</type>
+                <scope>import</scope>
+            </dependency>
+        </dependencies>
+    </dependencyManagement>
+
+    <dependencies>
+        <dependency>
+            <groupId>com.google.cloud</groupId>
+            <artifactId>google-cloud-vertexai</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>com.microsoft.semantic-kernel</groupId>
+            <artifactId>semantickernel-api</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+            <scope>compile</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-core</artifactId>
+            <scope>compile</scope>
+        </dependency>
+
+        <!-- Required for Android -->
+        <dependency>
+            <groupId>javax.xml.stream</groupId>
+            <artifactId>stax-api</artifactId>
+            <scope>provided</scope>
+        </dependency>
+    </dependencies>
+
+</project>

java/aiservices/google/src/main/java/com/microsoft/semantickernel/aiservices/google/GeminiService.java

@@ -0,0 +1,33 @@
+// Copyright (c) Microsoft. All rights reserved.
+package com.microsoft.semantickernel.aiservices.google;
+
+import com.google.cloud.vertexai.VertexAI;
+import com.microsoft.semantickernel.services.AIService;
+
+import javax.annotation.Nullable;
+
+public class GeminiService implements AIService {
+    private final VertexAI client;
+    private final String modelId;
+
+    protected GeminiService(VertexAI client, String modelId) {
+        this.client = client;
+        this.modelId = modelId;
+    }
+
+    @Nullable
+    @Override
+    public String getModelId() {
+        return modelId;
+    }
+
+    @Nullable
+    @Override
+    public String getServiceId() {
+        return null;
+    }
+
+    protected VertexAI getClient() {
+        return client;
+    }
+}