feat(ods): реализован ODS слой и DAG загрузки из STG

- Зачем:
  - подготовлена учебная реализация ODS слоя с типизацией, UPSERT и DQ, чтобы продолжить работу от STG к DDS/DM.
- Что:
  - добавлены SQL-скрипты `sql/ods/*_ddl.sql`, `sql/ods/*_load.sql`, `sql/ods/*_dq.sql` для 9 сущностей bookings.
  - добавлены DAG `bookings_ods_ddl` и `bookings_to_gp_ods`, а также smoke-тесты для новых графов.
  - ODS DDL интегрирован в `sql/ddl_gp.sql`; документация и план обновлены под единый запуск через `make ddl-gp`.
- Проверка:
  - `make test`.
  - `make ddl-gp`.

sql/ods/segments_load.sql

@@ -0,0 +1,75 @@
+-- Загрузка ODS по segments: SCD1 (UPDATE изменившихся + INSERT новых).
+
+-- Statement 1: UPDATE существующих строк.
+WITH src AS (
+    SELECT
+        s.ticket_no,
+        NULLIF(s.flight_id, '')::INTEGER   AS flight_id,
+        s.fare_conditions,
+        NULLIF(s.price, '')::NUMERIC(10,2) AS segment_amount,
+        s.src_created_at_ts                 AS event_ts,
+        ROW_NUMBER() OVER (
+            PARTITION BY s.ticket_no, s.flight_id
+            ORDER BY s.src_created_at_ts DESC NULLS LAST, s.load_dttm DESC
+        ) AS rn
+    FROM stg.segments AS s
+    WHERE s.batch_id = '{{ ti.xcom_pull(task_ids="resolve_stg_batch_id") }}'::text
+)
+UPDATE ods.segments AS o
+SET fare_conditions = s.fare_conditions,
+    segment_amount  = s.segment_amount,
+    event_ts        = s.event_ts,
+    _load_id        = '{{ ti.xcom_pull(task_ids="resolve_stg_batch_id") }}'::text,
+    _load_ts        = now()
+FROM src AS s
+WHERE s.rn = 1
+    AND o.ticket_no = s.ticket_no
+    AND o.flight_id = s.flight_id
+    AND (
+        o.fare_conditions IS DISTINCT FROM s.fare_conditions
+        OR o.segment_amount IS DISTINCT FROM s.segment_amount
+        OR o.event_ts IS DISTINCT FROM s.event_ts
+    );
+
+-- Statement 2: INSERT новых строк.
+WITH src AS (
+    SELECT
+        s.ticket_no,
+        NULLIF(s.flight_id, '')::INTEGER   AS flight_id,
+        s.fare_conditions,
+        NULLIF(s.price, '')::NUMERIC(10,2) AS segment_amount,
+        s.src_created_at_ts                 AS event_ts,
+        ROW_NUMBER() OVER (
+            PARTITION BY s.ticket_no, s.flight_id
+            ORDER BY s.src_created_at_ts DESC NULLS LAST, s.load_dttm DESC
+        ) AS rn
+    FROM stg.segments AS s
+    WHERE s.batch_id = '{{ ti.xcom_pull(task_ids="resolve_stg_batch_id") }}'::text
+)
+INSERT INTO ods.segments (
+    ticket_no,
+    flight_id,
+    fare_conditions,
+    segment_amount,
+    event_ts,
+    _load_id,
+    _load_ts
+)
+SELECT
+    s.ticket_no,
+    s.flight_id,
+    s.fare_conditions,
+    s.segment_amount,
+    s.event_ts,
+    '{{ ti.xcom_pull(task_ids="resolve_stg_batch_id") }}'::text,
+    now()
+FROM src AS s
+WHERE s.rn = 1
+    AND NOT EXISTS (
+        SELECT 1
+        FROM ods.segments AS o
+        WHERE o.ticket_no = s.ticket_no
+            AND o.flight_id = s.flight_id
+    );
+
+ANALYZE ods.segments;