Retain Leaders from Integrated Subjects & Pre-FTL Civilizations

Overview Have you ever wondered what happened to the former leaders of your subject after you integrated them? Or perhaps where that pre-FTL leader went after you annexed their planet? Wonder no more! With this mod you will be prompted to choose what to do with the now-unemployed leaders whenever you integrate a subject, conquer a pre-FTL planet, "allow" pre-FTLs to join you via covert infiltration, or convert then via a colossus weapon. Rulers demoted for any reason such as being integrated or even losing an election benefit by gaining the same former ruler traits. They may not have won the hearts and minds of voters, but they still rose to the occasion and developed new skills. This will applies when being demoted from ruler for any reason, such as gameplay from another mod. Regular (non-machine and non-hive) empires can retain leaders from an integrated Machine Intelligence subject if they have full AI rights. The leaders in a Machine Intelligence have enough capacity to act as independent agents, even if the rest of the Pops don't. Scientists and Admirals are automatically assigned back to their per-integration roles, if they were commanding a science ship or fleet. Notably, if you play with "pause-on-event" the science vessels will then continue their assigned orders after the leader is reassigned for command. Changes A lot of code has gone into figuring out what leaders you can choose to keep based on what kind of country you are playing, what ethics it has, what kinds of assimilation or necrophage might be available. All of that boils down to an event screen that appears when you have integrated a subject or conquered a pre-FTL planet, or a second event when you have infiltrated a pre-FTL planet. These event present you with a few choices about what you can do with the leaders from the now-defunct subject/pre-FTLs. It will show a few different options depending on what is available to you. For example, genocidal empires can only keep leaders that are of their