prepare: warn but don't fail on initialised db (bug 1956987)

[shtrom]

No description provided.

[Copilot]

Pull Request Overview

This PR updates the initialization behavior for the database, changing the flow so that an already initialized database logs a warning and returns early instead of raising an exception.

• Updated phabricatoremails/prepare.py to log a warning and early return when the database is already initialized
• Removed the unused DBInitializedError from phabricatoremails/db.py

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
phabricatoremails/prepare.py	Changed error handling to warn and return early if the database has already been initialized.
phabricatoremails/db.py	Removed the DBInitializedError exception which is no longer used.

Comments suppressed due to low confidence (1)

phabricatoremails/prepare.py:28

• Consider adding test cases to verify that the early return behavior properly handles cases where the database is already initialized.

return