feat: major update with network graphs, themes, todo extensions, and more

## New Features

### Network Graph Visualization (Contacts, Calendar, Todo)
- D3.js force simulation for physics-based layout
- Zoom & pan with mouse/touchpad
- Keyboard shortcuts: +/- zoom, 0 reset, Esc deselect, / search, F focus
- Filtering by tags, company/location/project, connection strength
- Shared components in @manacore/shared-ui

### Central Tags API (mana-core-auth)
- CRUD endpoints for tags
- Schema: tags table with userId, name, color, app
- Shared tag components in @manacore/shared-ui

### Custom Themes System
- Theme editor with live preview and color picker
- Community theme gallery
- Theme sharing (public, unlisted, private)
- Backend API in mana-core-auth

### Todo App Extensions
- Glass-pill design for task input and items
- Settings page with 20+ preferences
- Task edit modal with inline editing
- Statistics page with visualizations
- PWA support with offline capabilities
- Multiple kanban boards

### Contacts App Features
- Duplicate detection
- Photo upload
- Batch operations
- Enhanced favorites page with multiple view modes
- Alphabet view improvements
- Search modal

### Help System
- @manacore/shared-help-content
- @manacore/shared-help-ui
- @manacore/shared-help-types

### Other Features
- Themes page for all apps
- Referral system frontend
- CommandBar (global search)
- Skeleton loaders
- Settings page improvements

## Bug Fixes
- Network graph simulation initialization
- Database schema TEXT for user_id columns (Better Auth compatibility)
- Various styling fixes

## Documentation
- Daily report for 2025-12-10
- CI/CD deployment guide

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.env.development

@@ -57,12 +57,6 @@ STRIPE_SECRET_KEY=sk_test_YOUR_KEY
 STRIPE_PUBLISHABLE_KEY=pk_test_YOUR_KEY
 STRIPE_WEBHOOK_SECRET=whsec_YOUR_SECRET
 
-# Email (Brevo/SendinBlue) - GDPR compliant EU provider
-# Get your API key from https://app.brevo.com/settings/keys/api
-BREVO_API_KEY=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
-BREVO_FROM_EMAIL=noreply@manacore.app
-BREVO_FROM_NAME=Mana Core
-
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 # CHAT PROJECT
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