Pre-push code review flagged the inline `with suppress(OperationalError)`
ALTERs as silently eating real errors. The project still uses inline
init_db migrations (CLAUDE.md aspires to Alembic but the runtime path
is inline), so as a minimum: add a `_try_migrate` helper that
distinguishes already-applied (debug log) from genuine failures
(warning log). Apply it to the Zigbee-related migrations only — the
legacy ALTERs above remain unchanged in this commit's scope.
Pouzor
2a6140a6b1