Improve type definitions

[DanielSRS]

This PR aims to improve type checking, mostly when setting a transport function.

---

• With the current behaviour, transportOptions can be set to any value, and when setting a transport function, theres no verification if the required options are provided or if its types are correct

• With this changes, transportOptions type is inferred from the provided transport functions, enforcing the correct types and preventing any required options to be forgotten, liken when setting multiple transport functions

The most notable change in this PR is that transportFunctionType is now a generic type, to when previously creating a custom transport could be done like this:

var customTransport: transportFunctionType = (props) => {
  // Do here whatever you want with the log message
  // Eg. a console log: console.log(props.level.text, props.msg)
};

will now be like this:

var customTransport: transportFunctionType<{ myCustomOption: string }> = (props) => {
  // Do here whatever you want with the log message
  // Eg. a console log: console.log(props.level.text, props.msg)
};

---

• also, with better defined types, some validation code could be removed but thats beyond the scope of this PR

[alessandro-bottamedi]

@DanielSRS Wow, awesome job! I’m testing all the code, and there’s a modification to make in the fileAsyncTransport regarding the method checks, but really great work. To complete it, do you have any ideas on how to retrieve the levels types directly from the configuration instead of setting them manually?

[DanielSRS]

@alessandro-bottamedi Just added it

Now instead of doing:

const config = {
  levels: {
    trace: 0,
    info: 1,
    error: 2,
  },
};

var log = logger.createLogger<"trace" | "info" | "error">(config);

Providing the config should be enough. If not config is provided, the default ones are used instead

const config = {
  levels: {
    trace: 0,
    info: 1,
    error: 2,
  },
} as const;

var log = logger.createLogger(config);
log.trace // should be correctly typed

var defaultLog = logger.createLogger();
defaultLog.warn // also correctly typed