Card contract MVP: schema-validate symbol pools, exits, capital controls, and feature requirements

[phenomenoner]

Why

Cards are the core product artifact. v0.1 needs a concrete schema contract so the runtime can validate authoring inputs before replay or live-sim work begins.

Scope

• define concrete schema/model for card manifests
• cover these card concerns explicitly:
  • entry parameters
  • stop-loss / take-profit
  • intraday forced exit
  • symbol pool
  • capital controls
  • feature / synthesizer requirements
• document how deck/global policy can tighten or override card declarations

Acceptance criteria

• the card schema can represent the example gap-reclaim card cleanly
• card-level symbol pools are explicit inputs to subscription planning
• reusable time-series synthesis is referenced as a requirement, not reimplemented ad hoc inside each card
• version/provenance fields are preserved for replay receipts