feat(scripts): complete stack init + prod data import with date shift

Schema cleanup:
- Remove anubis_ua_rules table stub from 03_anubis_tables.sql
- Remove anubis_ua_rules from bot-detector deploy_schema.sql
- Remove UA seed step from clickhouse-init.sh (no more REGEXP_TREE dependency)
- Drop dict_anubis_ua, dict_anubis_country, anubis_ua_rules, anubis_country_rules

New scripts:
- scripts/init-stack.sh: comprehensive ClickHouse init (13 SQL files + migrations
  + validation + cleanup of obsolete tables). Supports --reset, --import-prod.
- scripts/import-prod-data.sh: imports pre-exported prod data (Native format)
  with dynamic date shift (max(time) → now). Supports --shift, --no-truncate.
- scripts/data/prod-export/: directory for cached Native format exports

Makefile targets: init-stack, import-prod-data, init-and-import

Tested: init-stack.sh passes all 13 SQL + 7 critical tables + 7 dicts
        import-prod-data.sh: 3M rows in ~37s with auto date shift
        Dashboard: 55 routes OK, bot-detector: 36/36 tests pass

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

.gitignore

@@ -33,3 +33,6 @@ bot_detector_logs/
 .vscode/
 .idea/
 *.swp
+
+# Exported prod data (large binary files)
+scripts/data/prod-export/*.native