Add portable capture and task model settings contracts

[callumalpass]

Summary

• add optional natural-language capture trigger configuration to the portable TaskNotes model
• round-trip trigger settings through the x-tasknotes type contract
• add a constrained, non-destructive task model settings patcher

Why

TaskNotes clients need one collection-owned source of truth for capture vocabulary and editable model behavior.

Validation

• npm test — 25 tests passed
• npm run test:package — package smoke passed