Task decomposition.

No structure

Linear tickets only

Structured doc-as-task with clear scope; each of at least `{investigation, feature, bug fix, tech research, spike}` has its own template with type-appropriate required fields (e.g. investigation templates include incident reference, reproduction steps, and timeline; feature templates include acceptance criteria and scope boundaries)

Past task structures inform new task templates; templates improve with use — template drift is tracked, recurring shapes produce reusable templates, and the template set itself evolves (new types added, stale ones deprecated)