import re

def normalize_log_line(line: str) -> str:
    """Strip timestamp/hostname noise from syslog-style line"""
    noise = re.compile(r"^\w{3}\s+\d+\s+\d{2}:\d{2}:\d{2}\s+[\w\-\.\:]+\s+")
    return noise.sub("", line).strip()

def keyword_search(content: str, query: str) -> list:
    """Case-insensitive keyword search across lines"""
    return [line for line in content.splitlines() if query.lower() in line.lower()]