Ignore invalid patterns when compiling full-regex sets

[KirtiRamchandani]

Problem

Full-regex filters are compiled lazily. When multiple compatible rules are optimized into a single pattern set, one invalid full-regex pattern can cause the whole RegexSet compilation to fail, which prevents valid patterns in the same set from matching.

Fixes #168.

Root cause

compile_regex returned CompiledRegex::RegexParsingError for the entire set whenever BytesRegexSetBuilder failed. That is correct for generated simple regexes, but too broad for full-regex filter lists where individual list entries may be unsupported or malformed.

Solution

When a full-regex set fails to compile, retry by keeping only patterns that compile individually. The remaining valid patterns are compiled as a single regex or regex set as appropriate. Non-full-regex generated sets keep the previous strict behavior.

Tests

• cargo fmt --all -- --check
• cargo test -p adblock invalid_complete_regex_does_not_disable_valid_pattern_in_set --lib --features full-regex-handling
• cargo test -p adblock regex_manager --lib --features full-regex-handling,debug-info
• cargo test -p adblock --lib --features full-regex-handling
• cargo test -p adblock --lib
• cargo clippy -p adblock --features full-regex-handling -- -D warnings
• git diff --check