[FEATURE] Add ability to ignore files if they don't exist

What / Why

Would be nice if there was a way to specify in the tar options to ignore files if they don't exist.

In my code, I am specifying a list of files that I want to compress into an archive, but it's in a dynamic directory so sometimes the files get removed. This will spit out an error with lstat saying that it does not exist.

When

Simply have an argument in the options table for tar.c

How

Could probably do it and have it almost like a "less strict" mode. When the file is being retrieved for the archive, have a checker that is like if(!fs.existsSync(file)) { return } or something.

Current Behavior

Feeding in a list of files in an array, and having one of them not exist will pass an error.

Expected Behavior

Having an option to specify something like ignoreNotFound should have it just ignore any entries in the array that do not exist.

Start at the tar.c entry point and inspect how the options table is handled and how missing files currently produce lstat errors. Define completion as an option that skips nonexistent entries while preserving normal errors for other failures, then verify the behavior with the existing test suite.