When recording new parentage information, always update the genepool as well as the active slave.  It's just newly-discovered information, not a real change to the slave.

Clean up extendedFamilyModeJS.js.  Mostly adding and correcting JSDoc for typesafety, but also removes the unused areTwins function, cleans up some predicate functions, and centralizes the logic of specificCharacterID.

VSCode and typescript still do not understand assignments to window as
introducing of a global name. To make them happy, use assignment to
globalThis.

Add setMissingParents function which makes sure slaves have parent IDs set before generating clones/siblings/etc.

2. Move NGP PC prep out of storyInit.tw into the newGamePlus closure
3. Move ngUpdateGenePool and ngUpdateMissingTable out from global scope into the newGamePlus closure
4. Set the NGP offset constant exactly once, in the newGamePlus closure
5. Fix some NGP bugs
6. Refactor family controller reset into resetFamilyCounters() in extendedFamilyModeJS.js, remove familyPanic.tw, and replace all other instances of family controller reset with a call to resetFamilyCounters().
7. Refactor revivalist nationality determination into a new getRevivalistNationality() function and call it everywhere we try to determine the revivalist nationality.

1. Make areRelated and relativeTerm work regardless of familyTesting.  This fixes some bugs right away, since they are already used unchecked a few places, and it makes it a lot easier to write generic descriptions and event text without breaking things.
2. Extend relativeTerm to handle sole parent and grandparent/grandchild cases.
3. Make relativeTerm return null instead of "some unknown blood relation" if no relationship could be found between two slaves.  This was never OK to output (i.e. "$his some unknown blood relation" doesn't read right), so it ended up just being tested for everywhere (which can be done more easily with null).
4. Remove duplicate code based on familyTesting when the only difference was whether areRelated and relativeTerm or their legacy alternatives were used.  There is a lot of this.
5. Remove hasRelationP entirely (it is superseded in all use cases by areRelated).

Significantly reduce the processing burden of showDistantRelatives (and fix a few bugs along the way)

Don't directly iterate the slavelist from slaveInteract in twinescript; do it in Javascript instead.