feat(web/settings): profile, tags, export, account deletion

[gracefullight]

Summary

• Profile page (/settings/profile): View avatar/email, edit display name via PATCH /auth/me
• Tags page (/settings/tags): Full CRUD with inline editing and color picker Popover (16 preset colors)
• Export page (/settings/export): CSV download of contacts with experiences via streaming endpoint
• Account page (/settings/account): Account deletion with AlertDialog confirmation (type "DELETE" to confirm)

Backend

• New tag table (migration 0004) with (user_id, name) unique constraint
• Tags CRUD endpoints: GET/POST /tags, PATCH/DELETE /tags/{id}
• Profile update: PATCH /auth/me
• Account deletion: DELETE /auth/me (cascades to contacts, tags)
• CSV export: GET /export/contacts (StreamingResponse)

Frontend

• Settings layout with tab navigation across 4 sub-pages
• 10 shadcn/ui components installed (button, input, label, badge, card, separator, avatar, alert-dialog, popover, tabs)
• Biome override for shadcn ui/ directory (label a11y rule)

Test plan

• Verify /settings redirects to /settings/profile
• Verify profile page loads user data and name can be updated
• Verify tags can be created, edited (name + color), and deleted
• Verify color picker popover opens and selects colors
• Verify CSV export downloads a valid contacts file
• Verify account deletion requires typing "DELETE" before confirming
• Verify tab navigation highlights active tab

🤖 Generated with Claude Code