fix: mcp_health capabilities KeyError; verify DATABASE_URL in init_db_pool

fix: move _servers_with_live_health before @router .get decorator; fix db try block indent

fix: correct indentation in db_pool try block

fix: log real PostgreSQL startup error instead of silently falling back

fix: agent/run direct provider chain; enable Supabase PostgreSQL via DATABASE_URL

production: clean source snapshot — no history bloat