- config.php: getDatabasePath() detects php built-in CLI server
(php_sapi_name() === 'cli-server') and routes to test.db; all
other SAPIs (nginx/fpm) get posterg.db. DB_ENV env-var still
overrides either way.
- migrate.sh: auto-initialise the target DB from storage/schema.sql
when the file is absent or has no tables yet. Existing DBs with
data are left completely untouched (table_count check, no re-run
of schema on populated DB). Idempotent: safe to run repeatedly.
- justfile: serve still calls migrate (which now handles init too),
no DB_ENV prefix needed since sapi detection handles routing.
