Release v1.24.3

docs(release): cut v1.24.3 changelog, upgrading, and roadmap.

Align README/INSTALL/DSN/CONTRIBUTING/ARCHITECTURE and specs 058/100 with auto reload-env and beacon-suite DB/long-content kinds.

Changelog

Changed

• Dogfood DX: make seed / make dogfood / make ready call reload-env-if-beacon-dsn-stale so php/messenger recreate when .env.local BEACON_DSN differs from the container (avoids ingest 401 after project recreate). New make reload-env recreates without Vite. See DSN.md.
• make beacon-suite: adds kinds db-sql, db-connection, and long-content (Query facts / connection errors / truncation). Spec 058 FR-015.

Notes for integrators

• No Doctrine migrations.
• After pull: no env changes required for local dogfood. Prefer make dogfood / make ready (auto reload). Manual: make reload-env.
• See UPGRADING.md Upgrading from 1.24.2 to 1.24.3.