Fix antlions using wrong angles for dynamic interactions

[Blixibon]

In the latest update, the functionality of interactions which don't use SCNPC_FLAG_TEST_OTHER_ANGLES was changed to make interaction partners continue to face their current angle, rather than face the angle stored in angRelativeAngles. This was done because there is no interaction in stock HL2/EP1/EP2 which doesn't use SCNPC_FLAG_TEST_OTHER_ANGLES, and the lack of that flag shouldn't force the interaction partner face a specific angle if it's not needed for the interaction to play.

The antlion interactions previously restored by Mapbase used angRelativeAngles, but did not use SCNPC_FLAG_TEST_OTHER_ANGLES. This is a hack which wouldn't have been possible with the actual model KV interaction syntax, and was done so that they could initiate the interactions at any angle while still correctly facing each other. However, this was not adjusted after the functionality of non-SCNPC_FLAG_TEST_OTHER_ANGLES interactions was changed, so they no longer face each other when initiating interactions.

The new flMaxAngleDiff value, which was also part of the latest update, allows for SCNPC_FLAG_TEST_OTHER_ANGLES interactions to initiate at broader angles, so by adding SCNPC_FLAG_TEST_OTHER_ANGLES and just setting that value to encompass any angle, it provides a "proper" way of doing what the antlion interactions did before.

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[1upD]

LGTM