request: Improve skip op/en to detect more chapter title variations locally

[luvsivy]

Checklist

• I checked that this feature has not been requested before
• I checked that this feature is not in the "Not planned" list
• This feature will benefit the majority of users

Problem Description / Use Case

The auto skip op/en doesn't work for most of my files cuz it only detects chapters literally named "OP" or "ED", my files have chapters named stuff like Opening, Ending, Intro, Credits, etc., and it just doesn't auto skip them. Since I download from different providers, they don't always use the same chapter names

Proposed Solution

Expand the chapter title to match more common variations like:

• Opening, Ending
• Intro, Outro
• Credits, End Credits
• case-insensitive matching so Opening, OPENING, opening all work

A regex or a predefined list of aliases would probably cover most cases without breaking anything

[nnotwen]

I checked that this feature has not been requested before

This is already addressed multiple times, there's this recently closed issue (#661). I also already reported this issue before here (#511). Basically, different release groups name their chapters differently, and using "Intro" as an alternative to "OP/Opening" to autoskip OP/EDs would mess up with some release group as there are chapters that are literally "Intro" that is not classified as OP/ED. Examples on (#511)

Personally, I'd rather manually skip the opening than miss an entire segment because it gets incorrectly flagged as Opening/Ending