feat: Google Calendar integration for achievement extraction

[nataliaherself]

Summary

Add Google Calendar integration to automatically extract achievements from meetings, strategy sessions, and collaboration moments.

Background

Competitive analysis of bragdocument.io revealed they offer Google Calendar integration as a key feature. This allows users to capture:

• Strategy sessions and planning meetings
• 1:1s with managers
• Incident response coordination
• Cross-team collaboration moments
• Presentations and demos

Currently, BragDoc focuses on code-based achievements (git commits, GitHub PRs, Jira). Adding calendar integration would capture the collaboration and leadership side of engineering work that doesn't show up in code.

Proposed Features

1. OAuth integration with Google Calendar API
2. Event metadata extraction (title, attendees, duration, recurrence)
3. AI-powered achievement detection - identify high-signal events (e.g., "Architecture Review", "Incident Postmortem", "Team Presentation")
4. Privacy-first approach - only extract metadata, never meeting notes/transcripts
5. User curation - review/approve calendar-derived achievements like existing workflow

Value Proposition

• Captures 30-40% of engineering impact that doesn't involve code
• Differentiates senior/staff engineers who spend more time in meetings
• Competitive parity with bragdocument.io
• Complements existing git/GitHub/Jira integrations

Technical Considerations

• Could be web-only integration (no CLI needed)
• Consider Microsoft Outlook/365 as future addition
• Rate limiting and quota management for Google API

Priority

Medium-High - This is a competitive gap identified in market analysis.

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Issue created from competitive analysis of bragdocument.io