BigBrain v0.26.0

Added

• Added optional Brain knowledge domains, with stable IDs, human-friendly names,
  and authoritative usage guidance stored in a Brain-specific domains.yaml
  registry.
• Added explicit MCP domain registry CRUD through domains/list,
  domains/get, domains/create, domains/update, and domains/delete.
• Added domain membership to page create, raw-file-with-page, and page update
  operations, while rejecting unregistered IDs and never auto-creating domains.
• Added dashboard graph domain filtering and domain-aware page previews.

Changed

• Made page tool schemas dynamically project the current domain registry through
  Zod, including each domain's guidance in the field description.
• Added health validation for invalid registries, unregistered memberships, and
  duplicate memberships.
• Made domain-scoped previews redact links to pages outside the selected domain
  at render time while preserving canonical Markdown unchanged.

Agent update actions

• Source installs: update to the v0.26.0 tag, run npm install, npm link,
  and npm run build:dashboard, then restart the BigBrain desktop, dashboard,
  and source-managed MCP services. Verify bigbrain sync --json,
  bigbrain health --json, MCP initialization, and npm test.
• No migration is required for existing pages, tasks, databases, or services.
  The domains page field is optional, and pages without it remain valid.
  Preserve and back up any existing Brain domains.yaml file with the Brain.
• If pages already contain domains memberships, ensure each ID is explicitly
  present in that Brain's registry or remove the membership, then run
  bigbrain sync --json and bigbrain health --json until the domain findings
  are clear. Do not invent registry entries during routine ingestion.
• Use domains/create, domains/update, and domains/delete only when the
  user explicitly curates the domain taxonomy. Use page tools only to assign
  already-registered IDs; the dynamic tools/list schema is the current source
  of available memberships and their guidance.
• Packaged desktop and standalone MCP installs should update together when
  practical, preserve Brain and database volumes, and verify the dashboard
  domain filter plus /health and /ready after restart.

Verification

• Serialized full test suite passed: 497 tests passed, 6 skipped because
  TEST_DATABASE_URL is not configured, and 0 failed.
• Dashboard production build passed.
• Local dashboard development smoke test passed with synthetic infrastructure,
  startup, and multi-domain meeting pages. Domain filtering returned the
  expected memberships, and scoped previews preserved in-domain links while
  rendering out-of-domain links as labels.