Add export helpers for browser import and other formats

[coreyleavitt]

Problem

Users often need to:

• Import passwords from browsers into kdbxtool
• Export from kdbxtool to browser-compatible CSV
• Convert between formats

Proposal

Add import/export utilities:

from kdbxtool import Database
from kdbxtool.export import to_csv, to_json, to_bitwarden
from kdbxtool.import_ import from_csv, from_chrome, from_firefox

# Export to CSV (Chrome/Firefox compatible)
db = Database.open('vault.kdbx', password='secret')
to_csv(db, 'export.csv', fields=['title', 'username', 'password', 'url'])

# Export to Bitwarden JSON
to_bitwarden(db, 'bitwarden-export.json')

# Import from Chrome CSV
entries = from_chrome('chrome-passwords.csv')
for entry in entries:
    db.root_group.add_entry(entry)

# Import from 1Password export
entries = from_1password('1password-export.csv')

Security Considerations

• Exported files contain plaintext passwords - should warn user
• Consider secure deletion of export files after import
• Maybe add encrypted export option?

Supported Formats

Priority:

1. Generic CSV (Chrome/Firefox/Edge compatible)
2. Bitwarden JSON
3. 1Password CSV
4. LastPass CSV

Labels

enhancement