- Removed 'saying goodbye' from CRITICAL tier (too common in innocent contexts)
- Narrowed 'wrote a will' to 'wrote a suicide note' (responsible behavior)
- Removed broad single-word matches from HIGH tier: give up, trapped, desperate, worthless, hopeless, no future, nothing left, can't see any light
- Added contextual HIGH tier phrases: feel hopeless, trapped in this, desperate for help, give up on life, etc.
- Updated MODERATE tier with contextual versions: feel worthless, feel hopeless, feel trapped, etc.
- Updated index.html JavaScript keywords to match Python changes
- Added comprehensive false positive test suite
All existing tests pass. New tests verify innocent messages no longer trigger false alarms.