mcp-memory-service: Missing Authentication on Document API Endpoints Allows Unauthenticated Memory Read/Write/Delete

mcp-memory-service is a semantic memory layer for AI applications. Prior to 10.67.1, all HTTP routes under /api/documents/* in mcp-memory-service are served without any authentication dependency, even when the server is configured with an API key (MCP_API_KEY) or OAuth. An unauthenticated remote attacker can upload arbitrary content into the memory store (write), retrieve stored document content (read), and permanently delete memories belonging to authenticated users (delete) — all without supplying any credentials. The /api/memories counterpart correctly enforces authentication, making this an inconsistent and exploitable authentication boundary. This vulnerability is fixed in 10.67.1.