Fix linking & library-overriding with NLA Tweak Mode enabled. This is a
two-pronged approach:
- When linking an animated ID from a library file, and it happens to be
in NLA Tweak Mode, it is forced out of tweak mode. This ensures that
the correct Action is loaded, and that all the NLA flags are set
correctly to display the NLA animation (instead of only the tweaked
strip).
- For library overrides there is now a post-process step that runs after
all 'apply' functions have been run. This is necessary to ensure that
all the flags and pointers that NLA Tweak Mode depends on are actually
set correctly and consistently.
This also adds one utility function `BKE_nla_debug_print_flags()` that
is by now unused. It was very useful in debugging this, though, and I
think it'll be useful in the future as well.
Design task: #120573
Pull Request: https://projects.blender.org/blender/blender/pulls/120830
910360637b