Verification report schema sync: align process template section contracts with docs-as-code schemas

## Problem
Template section descriptions and schema descriptions can drift.

## Scope v1
- Add canonical section contract fields in module/platform verification templates.
- Implement a docs-as-code sync gate for `verification_coverage`.
- Fail on drift.

## Out of scope
- Full metamodel ingestion in v1.
- All-section automation in v1.

## Acceptance criteria
- [ ] Module and platform verification templates expose canonical section contract fields.
- [ ] `verification_coverage` has a docs-as-code sync gate wired into CI.
- [ ] CI fails when template section contracts and docs-as-code schema definitions drift.
- [ ] Docs include brief guidance for maintaining schema/template alignment.