Feat centralized configuration for sea-orm-cli

[CCXLV]

New Features

Added support for a sea-orm.toml configuration file.

[database]
url = { env = "DATABASE_URL" }

[migrations]
directory = "./migration"

database.url - Can be a full database URL or a reference using the env to load the value from an environment variable.
migrations.directory - Relative path to the migration directory, resolved from the location of the config file.

This configuration file replaces the need to pass migration_dir and database_url as command-line arguments to sea-orm-cli.
It makes the CLI easier to use by centralizing configuration in one place and also opens the door for future features that rely on consistent config.

Changes

The sea-orm-cli migrate command no longer accepts the migration_dir and database_url arguments.
These are now fully handled through sea-orm.toml.

Usage

If the config file is missing, the CLI will show an error explaining that the project is not configured yet, and prompt the user to run:

sea-orm-cli config init

This command will automatically create a sea-orm.toml file in the current directory, prefilled with template values.
Users may then adjust the values as needed.

[Huliiiiii]

Wow, that was fast. Thanks for the quick update!