[Feature Request] MCP Support

Description

Add native Model Context Protocol (MCP) support to Paperless-ngx.

This would allow AI assistants such as ChatGPT, Claude, and other MCP-compatible clients to securely search and interact with a Paperless-ngx library.

Potential benefits:

• Search and retrieve documents using natural language
• Access OCR text and metadata
• Manage tags, correspondents, and document types
• Automate document ingestion and classification
• Standard integration instead of separate AI integrations

Downsides / concerns:

• Security and privacy are critical given the sensitive nature of stored documents
• Must respect existing Paperless-ngx permissions and authentication
• Write/delete operations would need careful authorization and confirmation

A sensible first implementation could be read-only MCP support for searching and retrieving documents, with write operations added later.

Other

_No response_