fix(sales): address review findings — 10 safe_auto fixes

- Fix pq-files using date-seq (daily) vs actual monthly parquet partitions
- Fix safe-cleanup-all destructure [[_ y m]] -> [[y m]] against [year month]
- Fix shutdown hook no-op: Thread wrapping #(fn []) now actually closes conn
- Fix query-deduped: PARTITION BY "external-id" not sales_order.external_id
- Fix :client_code -> :client-code key mismatch in get-payment-items-parquet
- Fix object-exists? downloading full S3 objects; use head-object instead
- Fix date-seq silently producing wrong range when start > end; now throws
- Remove duplicate private get-fees that shadowed public version
- Deduplicate date-seq: remove from sales_to_parquet, use p/date-seq
- Wrap run-perf-tests in (comment ...) to prevent execution on lein test
- Make month-seq public so sales_summaries.clj can use it

test/clj/auto_ap/storage/perf_test.clj

@@ -108,5 +108,6 @@
     (finally
       (p/disconnect!))))
 
-(run-perf-tests)
-(println "\n=== Done ===")
+(comment
+  (run-perf-tests)
+  (println "\n=== Done ==="))