Build a provenance-gated UK circuit and layout track pack #109

Parent: #105

Objective

Provide build-deployable JSON definitions for major permanent paved UK car circuits and their standard layouts.

Scope

• Cover England, Scotland, Wales, and Northern Ireland.
• Exclude kart-only tracks, hill climbs, temporary street circuits, and temporary airfield venues unless separately approved.
• Store start, finish, pit entry, pit exit, direction, thresholds, geofence, layout identity, revision, and provenance.
• Use public research only where licensing permits redistribution.
• Mark researched coordinates provisional until independently or physically validated.
• Prevent provisional definitions from silently claiming timing-ready status.
• Validate every file against schema and semantic rules in CI.
• Produce a manifest of circuits/layouts, sources, confidence, and missing validation.

Acceptance criteria

• The agreed major-circuit/layout manifest has a definition or an explicit documented blocker.
• Every committed definition passes automated validation.
• Provenance and validation status are machine-readable.
• No provisional geometry is presented as verified timing geometry.
• Build tooling packages the track files for offline device deployment.