fix: file system running in docker

[ankittk]

ISSUE: #98
The issue was that when MCPJungle runs inside a Docker container, the filesystem MCP server could only access files within the container, not the host machine's filesystem.

It uses npx @modelcontextprotocol/server-filesystem . runs with the container's working directory, which is typically / or the container's root. This means it can only access files within the container, not the host machine's filesystem.

Why?
The client.NewStdioMCPClient() function from the mcp-go library doesn't provide a way to specify the working directory for the subprocess, so it inherits the working directory of the parent MCPJungle process.

So if we modify the docker config to mount the host fs into the container and update the MCP server fs config to use the mounted path, this should fix this.

• Added volume mounts to both docker-compose.yaml and docker-compose-prod.yaml to mount the host filesystem at /host inside the container.
• Added readme + develoment instruction for docker filesystem
• Instead of storing filesystem.json in examples/ directory, we could simply use in README and DEVELOPMENT, users can copy paste and use directly as they are very simple and reduces maintenance, fewer files to manage too

[duaraghav8]

Replace this with When running mcpjungle directly on the host machine

[duaraghav8]

let's keep this code but comment it out, with a comment that tells the user to enable it if they want to mount.

This compose file is designed to be run on remote servers and by default, we shouldn't touch things outside docker boundary.
because production users will probably not use filesystem mcp server (filesystem is useful for running locally, so mostly individual users running mcpjungle for their personal use benefit from it)