v0.2.0 — Trader Execution Framework

New engine document trader-framework.md: execution dimensions, spread-vs-FV bands, liquidity tiers, thermometer overlay, Execution Decision Matrix. WP-TR-01 engine completion — development backlog cleared (16/16 paths, all roles have dedicated engines). Also: engine-overview/dev README history backfills, stale skill-reference statuses fixed. See CHANGELOG.md.