fix: resolve golangci-lint warnings

- Handle ignored errors with explicit _ assignment (errcheck)
- Add #nosec comments for false positive G304/G204 warnings (gosec)
- Fix misspelling: cancelled -> canceled

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

internal/storage/sqlite/queries.go

@@ -1178,12 +1178,12 @@ func (s *SQLiteStorage) executeDelete(ctx context.Context, tx *sql.Tx, inClause
 	for rows.Next() {
 		var id, issueType string
 		if err := rows.Scan(&id, &issueType); err != nil {
-			rows.Close()
+			_ = rows.Close()
 			return fmt.Errorf("failed to scan issue type: %w", err)
 		}
 		issueTypes[id] = issueType
 	}
-	rows.Close()
+	_ = rows.Close()
 
 	// 3. Convert issues to tombstones (only for issues that exist)
 	now := time.Now()