docs: add quickstart guide for MCP with Neo4j (#1774)

## Description

Samples for MCP with Neo4j for this page:
https://googleapis.github.io/genai-toolbox/samples/

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---------

Co-authored-by: Yuan Teoh <45984206+Yuan325@users.noreply.github.com>

docs/en/samples/neo4j/_index.md

@@ -0,0 +1,7 @@
+---
+title: "Neo4j"
+type: docs
+weight: 1
+description: >
+  How to get started with Toolbox using Neo4j.
+---

docs/en/samples/neo4j/mcp_quickstart.md

@@ -0,0 +1,141 @@
+---
+title: "Quickstart (MCP with Neo4j)"
+type: docs
+weight: 1
+description: >
+  How to get started running Toolbox with MCP Inspector and Neo4j as the source.
+---
+
+## Overview
+
+[Model Context Protocol](https://modelcontextprotocol.io) is an open protocol that standardizes how applications provide context to LLMs. Check out this page on how to [connect to Toolbox via MCP](../../how-to/connect_via_mcp.md).
+
+
+## Step 1: Set up your Neo4j Database and Data
+
+In this section, you'll set up a database and populate it with sample data for a movies-related agent. This guide assumes you have a running Neo4j instance, either locally or in the cloud.
+
+. **Populate the database with data.**
+To make this quickstart straightforward, we'll use the built-in Movies dataset available in Neo4j.
+
+. In your Neo4j Browser, run the following command to create and populate the database:
++
+```cypher
+:play movies
+````
+
+. Follow the instructions to load the data. This will create a graph with `Movie`, `Person`, and `Actor` nodes and their relationships.
+
+
+## Step 2: Install and configure Toolbox
+
+In this section, we will install the MCP Toolbox, configure our tools in a `tools.yaml` file, and then run the Toolbox server.
+
+. **Install the Toolbox binary.**
+The simplest way to get started is to download the latest binary for your operating system.
+
+. Download the latest version of Toolbox as a binary:
+\+
+
+```bash
+export OS="linux/amd64" # one of linux/amd64, darwin/arm64, darwin/amd64, or windows/amd64
+curl -O [https://storage.googleapis.com/genai-toolbox/v0.16.0/$OS/toolbox](https://storage.googleapis.com/genai-toolbox/v0.16.0/$OS/toolbox)
+```
+
+  + 
+. Make the binary executable:
+\+
+
+```bash
+chmod +x toolbox
+```
+
+. **Create the `tools.yaml` file.**
+This file defines your Neo4j source and the specific tools that will be exposed to your AI agent.
+\+
+{{\< notice tip \>}}
+Authentication for the Neo4j source uses standard username and password fields. For production use, it is highly recommended to use environment variables for sensitive information like passwords.
+{{\< /notice \>}}
+\+
+Write the following into a `tools.yaml` file:
+\+
+
+```yaml
+sources:
+  my-neo4j-source:
+    kind: neo4j
+    uri: bolt://localhost:7687
+    user: neo4j
+    password: my-password # Replace with your actual password
+
+tools:
+  search-movies-by-actor:
+    kind: neo4j-cypher
+    source: my-neo4j-source
+    description: "Searches for movies an actor has appeared in based on their name. Useful for questions like 'What movies has Tom Hanks been in?'"
+    parameters:
+      - name: actor_name
+        type: string
+        description: The full name of the actor to search for.
+    statement: |
+      MATCH (p:Person {name: $actor_name}) -[:ACTED_IN]-> (m:Movie)
+      RETURN m.title AS title, m.year AS year, m.genre AS genre
+  
+  get-actor-for-movie:
+    kind: neo4j-cypher
+    source: my-neo4j-source
+    description: "Finds the actors who starred in a specific movie. Useful for questions like 'Who acted in Inception?'"
+    parameters:
+      - name: movie_title
+        type: string
+        description: The exact title of the movie.
+    statement: |
+      MATCH (p:Person) -[:ACTED_IN]-> (m:Movie {title: $movie_title})
+      RETURN p.name AS actor
+```
+
+. **Start the Toolbox server.**
+Run the Toolbox server, pointing to the `tools.yaml` file you created earlier.
+\+
+
+```bash
+./toolbox --tools-file "tools.yaml"
+```
+
+## Step 3: Connect to MCP Inspector
+
+. **Run the MCP Inspector:**
+\+
+
+```bash
+npx @modelcontextprotocol/inspector
+```
+
+. Type `y` when it asks to install the inspector package.
+. It should show the following when the MCP Inspector is up and running (please take note of `<YOUR_SESSION_TOKEN>`):
+\+
+
+```bash
+Starting MCP inspector...
+⚙️ Proxy server listening on localhost:6277
+🔑 Session token: <YOUR_SESSION_TOKEN>
+    Use this token to authenticate requests or set DANGEROUSLY_OMIT_AUTH=true to disable auth
+
+🚀 MCP Inspector is up and running at:
+    http://localhost:6274/?MCP_PROXY_AUTH_TOKEN=<YOUR_SESSION_TOKEN>
+```
+
+1. Open the above link in your browser.
+
+1. For `Transport Type`, select `Streamable HTTP`.
+
+1. For `URL`, type in `http://127.0.0.1:5000/mcp`.
+
+1. For `Configuration` -\> `Proxy Session Token`, make sure `<YOUR_SESSION_TOKEN>` is present.
+
+1. Click `Connect`.
+
+1. Select `List Tools`, you will see a list of tools configured in `tools.yaml`.
+
+1. Test out your tools here\!
+