fix lint issues across codebase

tests/test_abuse_prevention.py

@@ -37,14 +37,14 @@ class TestContentDedup:
         # First 3 submissions should succeed
         for i in range(3):
             response = strict_client.post("/", data=content)
-            assert response.status_code == 201, f"Submission {i+1} failed"
+            assert response.status_code == 201, f"Submission {i + 1} failed"
 
     def test_duplicate_exceeds_threshold_rejected(self, strict_client):
         """Fourth duplicate within window should be rejected."""
         content = b"unique content 3"
 
         # First 3 succeed
-        for i in range(3):
+        for _ in range(3):
             response = strict_client.post("/", data=content)
             assert response.status_code == 201
 
@@ -144,8 +144,7 @@ class TestContentHashDatabase:
         # Query database directly
         db = get_db()
         row = db.execute(
-            "SELECT hash, count FROM content_hashes WHERE hash = ?",
-            (content_hash,)
+            "SELECT hash, count FROM content_hashes WHERE hash = ?", (content_hash,)
         ).fetchone()
 
         assert row is not None
@@ -179,10 +178,7 @@ class TestContentHashCleanup:
 
         # Verify removed
         db = get_db()
-        row = db.execute(
-            "SELECT * FROM content_hashes WHERE hash = ?",
-            (content_hash,)
-        ).fetchone()
+        row = db.execute("SELECT * FROM content_hashes WHERE hash = ?", (content_hash,)).fetchone()
         assert row is None
 
     def test_cleanup_keeps_recent(self, app_context):
@@ -193,14 +189,11 @@ class TestContentHashCleanup:
         check_content_hash(content_hash)
 
         # Cleanup should not remove it
-        deleted = cleanup_expired_hashes()
+        cleanup_expired_hashes()
 
         # Verify still present
         db = get_db()
-        row = db.execute(
-            "SELECT * FROM content_hashes WHERE hash = ?",
-            (content_hash,)
-        ).fetchone()
+        row = db.execute("SELECT * FROM content_hashes WHERE hash = ?", (content_hash,)).fetchone()
         assert row is not None
 
 
@@ -268,6 +261,7 @@ class TestEntropyEnforcement:
     def test_random_data_accepted(self, entropy_client):
         """Random/encrypted data should pass entropy check."""
         import os
+
         random_data = os.urandom(512)  # High entropy random bytes
 
         response = entropy_client.post(