So, I've kinda/sorta figured out how to create a Ship Module or Planet Improvement to generate either strategic or luxury resources. It doesn't show as attached to the planet as I haven't figured out yet how to create and/or trigger an anomaly, but it gets the job done. Unfortunately, there are some luxuries that don't work for some reason. Out of 24, I've been able to have the game register and produce 16. They all show on the planet screen, but not the Trading screen. 

-KnyghteFall

If you want to make all luxurys available just open the file Public/Settings/WorldSettingDefinitions.xml and set all 

<KeyValuePair Key="LuxuryResourceCommonTypes">8</KeyValuePair>
<KeyValuePair Key="LuxuryResourceUncommonTypes">8</KeyValuePair>
<KeyValuePair Key="LuxuryResourceRareTypes">8</KeyValuePair>

To 8 as shown, there are 7 copys of these keyvaluepairs, one for each galaxy size.

Warning: this may mess up the selling GUI part of the marketplace screen.

To Knyghtefall, The way that the galaxy generation works is that it picks at the very start which luxurys are enabled & which are disabled.

disabled luxurys can't appear in the market place or be used in empire development. 

I'm currently looking through the .NET Assemblies EndlessSpace2_Data\Managed\Assembly-CSharp.dll & Assembly-CSharp-firstpass.dll I will let you know if I find anything relevant

Edit:

I have no Idea if anyone else here is looking around the Assemblies but in case they are here is what I've found:

In Assembly-CSharp.dll / - / namespace Generator.Tasks / public class DistributeCuriosities /  private void MakeDepositFromSlot(Slot slot, string resourceName,  bool visible);

Is the code that adds deposits to planets, I've looked at what classes use this class and what classes use those etc. I can't see a way of adding a deposit other than during galaxy generation

In Assembly-CSharp.dll / - / public class Game / private sealed class <OnIgnite>c__Iterator7 /  private void ExecuteFactionTraitCommand (Empire empire, FactionTrait.Command command)

This is what controls the abilities of the <command> tag in the XML so if the Assembly is edited (which is by no means easy) new functionality can be added even possibly adding the ability to spawn in new resource deposits)

Hmmm in 1.0.16 even with everything set to 8 still wind up 3 luxury resources short every time...  Always seems to be luxury resources 9 13 and 24 missing.