Ensure color column exists before query in legacy DB migration

[jayaddison]

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• I am following the Code Style Guidelines
• I have tested my contribution on these devices:

• Device A, Android X.Y.Z
• Device B, Android Z.Y
• Virtual device W, Android Y.Y.Z

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Description

I have an old-ish Android 6.x device that I previously used Signal on. The database schema has gotten into a state where the updateSystemContactColors migration fails due to a missing color column on the recipient table.

The failure prevents the Signal user interface from opening, locking me out of historical conversations and media I'd like to retain.

That database migration has been deprecated since Y2021 (ref: bcc5d48).

This pull request adds an error-ignored step to add the column before it is queried (as far as I know, SQLite has no add column if not exists functionality). I have not yet tested this, but believe that it would solve the problem.

I have not been able to decrypt the database from my device to test this with, and I am not keen to root the device purely to install an unsigned test build.

May resolve #14228.