validate: diff generated SQL against FoodFiles v2 existing migrations

[stackbilt-admin]

cc-task queued to write FoodFiles contracts (task a2caf991). Once complete, run generateSQL() against each FoodFiles contract and diff output against apps/api/db/migrations/ files.

The delta reveals generator accuracy. Track:

• Column types
• CHECK constraints
• Indexes
• Foreign keys
• Defaults

This is the primary feedback loop for generator tuning.