feat (file-name-matches-element): new rule

[43081j]

Enforces that the filename of a file containing a custom element matches its class name according to the configured conventions.

For example, the default is ['kebab', 'camel'] which means the following examples are true:

// valid filename: someElement.js
// invalid filename: some_element.js
class SomeElement extends HTMLElement {}

With matchDirectory: true set:

// valid filename: foo/bar/someElement.js
// valid filename: bar/someElement.js
// valid filename: fooBarSomeElement.js
// invalid filename: some_element.js
class FooBarSomeElement extends HTMLElement {}

cc @keithamus this was probably the most difficult one. its not a lot of logic but getting my head around the various nested pieces of logic took a while 😂

but its the last one! 🎉

[keithamus]

Nice work!