MCP server: add a tool to upload images for use in articles and assets

Problem
The MCP server can create and edit KB articles, but it cannot upload images. External AI clients such as Claude and ChatGPT don’t pass chat attachments to MCP servers, so the attachment:// references in the article tools only work in Hudini. The documentation also lists uploading public photos as not supported.

As a result, an AI client can write a complete how-to article but can’t add the screenshots. For end-user documentation the screenshots are the most important part, so every article still needs manual work in the editor.

Proposed solution
Add a tool such as public_photo_create_tool that accepts an image (base64 or multipart) plus an optional record type and ID, and returns the /public_photo/<slug> path. The article and asset tools already accept those paths, so no other changes are needed.

Why this is a small change
The building blocks already exist. Hudini can embed attached images, and article content with inline image data is already converted to public photos on save. Exposing that as a dedicated tool would make it reliable for every MCP client.

Use case
As an MSP, we create generic, client-facing KB articles with screenshots. With this tool, the full article including images could be created from an AI client in one step.