Remove redundant 'Z' suffix from isoformat() - timezone-aware
datetimes already include +00:00 offset, so appending 'Z' created
invalid RFC3339 timestamps that Google Calendar API rejected.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Implements cost-efficient gmail operations by delegating to appropriate
model tiers via Claude CLI subprocess. Simple fetches use no LLM,
summarization and triage delegate to Sonnet, complex reasoning stays
with Opus (PA). Uses subscription instead of API key.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>