v1.0.0

Initial release.

• pgdrift snapshot — capture schema to JSON
• pgdrift diff — categorized change report (BREAKING / ADDITIVE / INFORMATIONAL / SCHEMA-LEVEL)
• pgdrift watch — poll for drift, exit 1 on BREAKING changes
• pgdrift report — rich terminal table view of any snapshot
• pgdrift demo — end-to-end demo against acme-parts-cloud
• 37 tests, zero live DB required in CI