adjust episode path expression to allow digits in series names

[senritsu]

Changes
The previous expression was too greedy to consume digits, because the hyphen was optional. This lead to incorrect episode numbers for certain series with digits in their names, in those cases each episode was recognized as the same episode number (the digit from the series name).

The rule, which matches most standard anime filenames, also had a lower priority than one of the Kodi rules, leading to incorrect recognition for absolute numbered episodes with triple digits and higher (first digit was used as season number, rest of digits as episode number). This also resolves one of the TODO test cases.

Additional test cases were added to ensure that both hyphens in different parts of the filename, as well as names without hyphens, still work correctly. All previous test cases still pass.

Unfortunately another TODO (EpisodeNumberTests.cs@L76, Uchuu Senkan Yamato 2199) with the same issue (digits in the series name) could not be trivially fixed in the same change, due to the significantly different formatting. Attempts to resolve this case did not work out for now.

Issues

[senritsu]

PS: Another triple-digit case from a fairly new comment (EpisodeNumberTests.cs@L73, Case Closed 317) was moved to the unit test TODOs, the expression where the filename was added to did not actually correctly match the filename, it resolved to season 3 episode 17. This did not seem to be the intent, given the folder name.