todoapp-core

The domain core of tda: entities, capabilities, and the ports (traits) that adapters implement. No I/O, no runtime, no framework dependencies — this crate compiles without touching a filesystem, a network, or an async runtime executor.

• Task = a stable identity (id + timestamps) plus a set of capabilities (Status, Notes, Schedule, Estimate, Tags, Assignment, Recurrence, IssueRef, Attachments, Archived, TimeLog) — composition instead of a fixed field list. See tda-spec.md §3.
• The decider pattern: decide (capability-keyed guards, first denial wins) → Events → apply (capability-keyed state changes). See tda-spec.md §5a.
• Ports (ComponentStore, TaskEntityStore, …) are defined here and implemented by adapters (todoapp-store-mem, todoapp-store-turso).

This crate sits at the bottom of the dependency rule: adapters → app → core. Nothing above may leak into it — this is enforced by mise run lint (lint:core-no-io, a cargo tree denylist).

See the root README and tda-spec.md for the full picture; CLAUDE.md for contributor conventions.