Unify objectives language in public facing places

[MjnMixael]

In FRED and QtFRED I noticed that the Mission Goals dialogs use the terms "goals" and "objectives" interchangeably. It's not clear why and it can cause confusion because "goals" can also refer to AI Goals. The goal objective of this PR is to unify around a single term to minimize confusion, which aligns with one of my core goals objectives for QtFRED; making mission design more accessible.

With this PR in place we have

• Directives: mini tasks given to the player during missions and shown on the HUD
• Objectives: major tasks given to the player during the mission briefing, shown in the Objectives screen during missions
• Goals: tasks given to AI ships to cause certain behaviors

This is almost exclusively a public facing change only; that is in editors, the Lua API, and the sexp names. Internal code such as enum & variable names, and file names should probably be changed at some point so that coder language matches user language, but that can come later and in smaller chunks. Doing that here would be an unnecessarily large PR.

This PR does add two API changes. First, there is a new ADE_INDEXER_DEPRECATED to match the existing versions of Func and Virtvar. I copied the methods from those directly. Second, there is a new path in missionsave.cpp that will use the old sexp string names in place of the new if we're saving in retail format. I was surprised this didn't exist before, so there may be other sexps that were renamed over the years that may benefit from this as well.

[MjnMixael]

This will need help dialog updates to unify language

Done

[JohnAFernandez]

shudders

[MjnMixael]

Not sure what was intended by this comment but I found some other things with the help text that needed addressing as well as a sexp I missed (reset-goal -> reset-objective).

[JohnAFernandez]

Still "mission_goal" here?

[MjnMixael]

yup. Done

[BMagnu]

Thanks for your patience on this. Internally, the SCP team has debated this for a bit now.
It's definitely useful to discuss possible QoL updates, though to be frank, we're a rather hesitant on the implementation of this PR.
Given the cost benefit considerations, we think this messes a bit too much with established FREDing.
Unfortunately, this would cause major issues with trying to follow the established and commonly referenced FREDing tutorials, especially with QtFRED changing parts of the UI, and the language being different.
It renames some very, very old (including retail!) and crucial SEXPs, causing people who are used to these to have to search and guess what they want. As an final note, scripting deprecation are always to be avoided unless there's a fundamental underlying technical reason for it that makes it unavoidable.

Personally, I think the idea is not wrong, but the implementation is way too invasive.
It'd be fine to leave the API's and SEXPs as is, and enhance the labels and help texts to strictly say "AI Goals" or "Mission Goals / Objectives" instead of just "Goals"

[MjnMixael]

Thanks for your patience on this. Internally, the SCP team has debated this for a bit now. It's definitely useful to discuss possible QoL updates, though to be frank, we're a rather hesitant on the implementation of this PR. Given the cost benefit considerations, we think this messes a bit too much with established FREDing. Unfortunately, this would cause major issues with trying to follow the established and commonly referenced FREDing tutorials, especially with QtFRED changing parts of the UI, and the language being different. It renames some very, very old (including retail!) and crucial SEXPs, causing people who are used to these to have to search and guess what they want. As an final note, scripting deprecation are always to be avoided unless there's a fundamental underlying technical reason for it that makes it unavoidable.

Personally, I think the idea is not wrong, but the implementation is way too invasive. It'd be fine to leave the API's and SEXPs as is, and enhance the labels and help texts to strictly say "AI Goals" or "Mission Goals / Objectives" instead of just "Goals"

I think that's a fairly shortsighted take and likely led by a particular SCP member who has a hard time with change. As one of the most active contributors to SCP it would be nice to be a part of these sort of discussions but I get that there are members who don't particularly want my opinions for whatever reason.

QtFRED is designed to have a whole new set of tutorials linked directly into it's help documentation and if we were ever going to unify around a common set of terms for the community going forward, now would be the time. This community lives and dies by making it easier for new members to get into making missions. This kind of thing lowers that barrier significantly.

However, I'm working hard to finish one of the biggest SCP projects yet and will choose to just let this go instead trying to argue the point with a group that doesn't want to hear my position.