Add Notion Brain collector

[mrubens]

What changed

• add a Brain collector for pages shared with the deployment Notion integration
• backfill pages newest-first and keep edits current with durable incremental cursors
• use the native Notion Markdown endpoint with stable Brain page slugs and source dates
• reconcile newly shared older pages with a daily full sweep
• reuse a shared Notion API client for the MCP tools and collector
• document Notion Brain ingestion

Why

Connected Notion knowledge was available to individual tasks through MCP, but it was not included in the shared Brain. This makes explicitly shared Notion pages available during Brain retrieval while retaining Notion permission boundaries.

Validation

• BullMQ Brain collector tests
• native Notion MCP auth tests
• Notion API client tests
• package TypeScript checks for SDK, API, and BullMQ
• targeted ESLint
• full pre-push oxlint, residual lint, fast typechecks, and Knip
• git diff checks

[roomote-community]

No new code issues found. See task

• Revoked Notion shares remain in the Brain because completed sweeps never reconcile missing pages. (apps/bullmq/src/scheduled-jobs/brain-collectors.ts:2418)

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