Toggle: auto-offset first section / sticky elements under a sticky header

[jackgranatowski]

Idea

An admin toggle that, on pages with a sticky/overlay header, automatically adds top offset to the first section and/or positions sticky elements below the header using the framework's --sf-header-height, with a per-header/per-page exclusion list.

Why

The framework exposes header-height and sticky-offset tokens, but applying the "push content below the sticky header" behaviour automatically is builder/site logic. Doing it by hand is a common first-run footgun.

Scope

• Setting to enable auto first-section offset + sticky-under-header, using --sf-header-height.
• Exclusion selectors for headers/pages that shouldn't offset.

Acceptance

• Toggle offsets first section + sticky elements under the header; exclusions honoured