Merge food metadata when seeding

[sevmonster]

First Check

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Please provide a concise description of the problem that would be addressed by this feature.

When seeding, foods are not updated if they exist in the seed data. Recently a lot of plurals were updated in the data—previous iterations of the data either had wrong plurals or missing values. This leaves a lot of potentially desirable data unavailable to people with pre-seeded foods.

It would be helpful to update fields of existing foods from the seed data.

Please provide a concise description of the feature that would resolve your issue.

• Update plural_name field from seed, even if already set
• Update description field if it isn't set (user-set value should be preferred)
• Merge aliases arrays

Please consider and list out some caveats or tradeoffs made in your design decision

Could have toggles to overwrite fields, if seeded fields would be preferred over existing data.

Additional Information

• If this is accepted I'm willing to submit a PR to provide this feature
• If this is accepted I'm willing to help maintain this feature
• I'm willing to sponsor/pay a developer to do this work