feat: an unpaid cart's files are kept 2 days, a paid order's 30

Files are uploaded before payment so the price and the security check use
the file itself, but an abandoned cart kept them for 30 days. Now a finished
upload is held 2 days, a quote waiting for review 7, an approved quote 2 more
to be paid, and the paid order keeps its originals for 30 days from upload.
A payment never starts for files that are gone; one under way holds them a
day. Files attached to an order take the order's window.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

app/payments.py

@@ -49,6 +49,26 @@ def is_test(order):
     return (order.get('payment') or {}).get('provider') == TEST_PROVIDER
 
 
+# How long a file is kept while nothing has been paid for it. A cart's files
+# are uploaded before payment, so the price and the security check are done on
+# the file itself; a cart that is never paid must not keep them for 30 days.
+UNPAID_HOLD = '2 days'
+# A quote waiting for an operator's review keeps its files this long.
+REVIEW_HOLD = '7 days'
+# Once paid, the order keeps its originals for this long from the upload.
+ORDER_RETENTION = '30 days'
+
+
+def quote_uploads(quote_or_draft):
+    return [uid for item in quote_or_draft['items'] for uid in item['uploads']]
+
+
+def hold_uploads(c, upload_ids, interval):
+    """Keep these files at least `interval` from now; never shortens a hold."""
+    c.execute('''UPDATE dtf_local.uploads SET expires_at=GREATEST(expires_at, now()+%s::interval)
+        WHERE id=ANY(%s) AND purged_at IS NULL''', (interval, [str(u) for u in upload_ids]))
+
+
 def create_order(c, quote, payment):
     """Create the order for a reviewed quote, or return the one already there.
 
@@ -68,6 +88,9 @@ def create_order(c, quote, payment):
     order = c.execute(
         'INSERT INTO dtf_local.orders(id,quote_id,owner,snapshot,payment) VALUES(%s,%s,%s,%s,%s) RETURNING *',
         (uuid4(), quote['id'], quote['owner'], Jsonb(approved), Jsonb(payment))).fetchone()
+    # Paid: the files are kept for the order's retention, counted from upload.
+    c.execute('''UPDATE dtf_local.uploads SET expires_at=GREATEST(expires_at, created_at+%s::interval)
+        WHERE id=ANY(%s) AND purged_at IS NULL''', (ORDER_RETENTION, quote_uploads(approved)))
     queue_print_files(c, order['id'], len(approved['items']))
     if is_test(order):
         return order, True