feat: add auto-migrations on startup

[Kenshiin13]

Description

Introduces a migration system for ESX that allows adding database migrations for older versions.
Includes a new migration for v1.13.3 that adds a unique ssn column to the users table, backfills existing users, and ensures the column is NOT NULL.

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Motivation

Previously, migrating users between ESX versions required manual SQL updates and ad-hoc scripts, which was error-prone and time-consuming.
This new system standardizes migrations, allows safe execution, and can be extended to handle migrations for any older ESX version.

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Implementation Details

• Migrations are registered in a Migrations table keyed by ESX version.
• Each migration is a Lua function that executes SQL updates and any necessary data transformations.
• The runner iterates through all migrations for a given version and executes them.
• Each completed migration is tracked using GetResourceKvpInt to avoid re-running on server restart.

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PR Checklist

• My commit messages and PR title follow the Conventional Commits standard.
• My changes have been tested locally and function as expected.
• My PR does not introduce any breaking changes.
• I have provided a clear explanation of what my PR does, including the reasoning behind the changes and any relevant context.