Update parse_filter_hosts.rs

[ZeroHack01]

🎯 Enhanced Fuzzing Target for Adblock Parser

What Changed

Improved the fuzzing target to provide better code coverage and robustness for finding edge cases in the adblock filter parser.

Key Improvements

• Multiple FilterFormats: Tests Standard, Hosts, and AdblockPlus (was only Hosts)
• Input Validation: Added bounds checking to prevent hangs on large inputs
• Panic Safety: Added catch_unwind protection
• Better Coverage: Tests common filter prefixes (||, @@, ###, etc.)
• Proper Error Handling: Processes parse results instead of ignoring them

Before

// Only tested FilterFormat::Hosts, no input validation
fuzz_target!(|data: &[u8]| {
    if let Ok(filter) = std::str::from_utf8(data) {
        parse_filter(filter, true, ParseOptions {
            format: FilterFormat::Hosts,
            ..Default::default()
        }); // Result ignored
    }
});