Don't warn about incompatible DLCs, fix conflict highlighting with DLC installed

[HebaruSan]

Problems

Similarly, this can appear for a mod that was incompatible when you installed it but has since become compatible (because it's on SpaceDock and someone put in a ksp_version_min override).

Also if you have any DLC installed and you click to install two conflicting mods, they aren't highlighted red.

Cause

SQUAD didn't update the MH version number correctly (flashbacks to the extra whitespace for the other DLC in #3243). Current GameData/SquadExpansion/MakingHistory/readme.txt:

*****************************************************************************************************
      __ _______ ____     __  ___      __   _               __  ___      __ 
     / //_/ ___// __ \   /  |/  /___ _/ /__(_)___  ___  _  / / / (_)____/ / ____ 
    / ,<  \__ \/ /_/ /  / /|_/ / __ `/ //_/ / __ \/ __ `/ / /_/ / / ___/ __/ __ \/ ___/ / / /
   / /| |___/ / ____/  / /  / / /_/ / ,< / / / / / /_/ / / __  / (__ ) /_/  /_/ / /  / /_/ /
  /_/ |_/____/_/      /_/  /_/\__,_/_/|_/_/_/ /_/\__, / /_/ /_/_/____/\__/\____/_/   \__, /  
                                                /____/                              /____/ 
 
*****************************************************************************************************

Thank you for downloading the Making History Expansion for Kerbal Space Program!

Version 1.11.0

...

ChangeLog:
=================================== v1.11.1 - Requires KSP v1.11.1 ================================
+++ Bugfixes
* Fix the servicemodules shielding antennae on launch when the shrouds are turned off.
* Fix KAL being unselectable in action pane in the mission builder.
* Fix the missing Robotics icon category in the action pane.
* Fix surface attachment issues with the LV-Tx87 Bobcat.

Since the Version 1.11.0 line is what CKAN uses to detect DLC versions, CKAN thinks everyone using MH on 1.11.1 has an incompatible DLC.

When selecting conflicting rows, ModuleIsDLCKraken is thrown here, because the resolver is being told to install DLC:

CKAN/GUI/Model/ModList.cs

Lines 483 to 488 in b748670

	var resolver = new RelationshipResolver(
	mods_to_check,
	change_set.Where(ch => ch.ChangeType == GUIModChangeType.Remove)
	.Select(ch => ch.Mod),
	options, registry, ksp_version
	);

Changes

• Now the incompatible modules warning excludes DLCs.
• Now the incompatible modules warning excludes mods with compatible metadata in the available modules list but incompatible metadata in the installed modules list.
• Now the main mod list grid conflict detector doesn't pass installed modules to the resolver, since it gets them from the registry itself anyway. This means that DLC will never be in its to-install list.

Fixes #3302. Fixes #3269.

[HebaruSan]

@SliceofLie, if you want to try this out, there's a test build at the bottom of this page:

https://github.com/KSP-CKAN/CKAN/actions/runs/593969600

[DasSkelett]

Hm, why is installed even contained in modules_to_check->modulesToInstall? The RelationshipResolver already considers them when checking for conflicts, using registry.InstalledModules in the end as well:

CKAN/Core/Relationships/RelationshipResolver.cs

Lines 250 to 251 in d3624b9

	//Need to check against installed mods and those to install.
	var mods = modlist.Values.Concat(installed_modules).Where(listed_mod => listed_mod.ConflictsWith(module));

CKAN/Core/Relationships/RelationshipResolver.cs

Line 118 in d3624b9

installed_modules = new HashSet<CkanModule>(registry.InstalledModules.Select(i_module => i_module.Module));

[HebaruSan]

I suspect that our assumptions about handling of installed modules changed over time in the resolver, and ModList.ComputeConflictsFromModList wasn't updated to reflect those changes. My goal was to find the smallest change to minimize the risk of unexpectedly breaking something else, but we can try something more drastic if you think it's a good idea.

[DasSkelett]

I think the impact of a slightly misbehaving ComputeConflictsFromModList would be limited.

But testing it everything seems to work as expected, conflicts with already installed modules get shown, as well as conflicts between two modules in the changeset about to be installed.
The RelationshipResolver of the actual install flow seems to work the same, with only the new modules in moduleToInstall.

So we should be fine removing installed from modules_to_check here.

[HebaruSan]

OK, will do. There's also some unnecessary conversion from CkanModule to identifier back to CkanModule here that could cause its own problems down the line, so might as well clean that up too.

[HebaruSan]

Done; now this looks very similar a block in MainInstall.cs, maybe we can consolidate them at some point...

[DasSkelett]

Nice!