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>

shared/clickhouse/03_anubis_tables.sql

@@ -1,29 +1,10 @@
 -- =============================================================================
 -- 03_anubis_tables.sql — Anubis crawler rule tables and dictionaries
--- Only IP/CIDR and ASN rules are populated by fetch_rules.py.
--- UA and Country dictionaries are kept as stubs (required by MV references)
--- but are never populated with real data.
+-- Only IP/CIDR and ASN rules are used. UA and Country have been removed.
 -- =============================================================================
 
 -- -----------------------------------------------------------------------------
--- 1. TABLE SOURCE — User-Agent rules (REGEXP_TREE stub)
--- REGEXP_TREE requires ≥1 rule; the catch-all is seeded at init time.
--- This table is NOT populated by fetch_rules.py.
--- -----------------------------------------------------------------------------
-CREATE TABLE IF NOT EXISTS ja4_processing.anubis_ua_rules
-(
-    id        UInt64,
-    parent_id UInt64,
-    regexp    String,
-    keys      Array(String),
-    values    Array(String)
-)
-ENGINE = ReplacingMergeTree()
-ORDER BY id;
-
-
--- -----------------------------------------------------------------------------
--- 2. TABLE SOURCE — IP/CIDR rules (for IP_TRIE dictionary)
+-- 1. TABLE SOURCE — IP/CIDR rules (for IP_TRIE dictionary)
 -- Populated by fetch_rules.py from Anubis GitHub data.
 -- -----------------------------------------------------------------------------
 CREATE TABLE IF NOT EXISTS ja4_processing.anubis_ip_rules