Add background/async mode to biblio_docling MCP tool

Goal

(promoted from note)

Context

(see source note)

Prompt

Read the idea at /storage2/arash/projects/projio/docs/log/idea/idea-arash-20260326-155537-817950.md. Implement option 1: add a background=True parameter to biblio_docling that returns a job ID immediately, plus a biblio_docling_status(job_id) companion tool. Use subprocess to run docling in the background. Store job state in .projio/biblio/jobs/. Work in packages/biblio/ for the core logic and src/projio/mcp/ for the MCP tool wrappers.

Acceptance Criteria

• [ ]

Result

(pending)