Disable asserts in CalculateTangentArray (discussed with davep) to avoid debugging interruptions from bad assets

MAINT-2632 speculative guards in display_startup based on prevalence of crashes ending there (no repro, unfortunately)

Fix issues with NaNs in tangent data from using normalize3fast on zero-length vectors and other data conditioning; also added assert to normalize3fast to make finding these problems easier in the future

NORSPEC-258 and NORSPEC-226 make tex picker close refresh build tool UI correctly and fix issues with transition from no-bumps to normal maps

NORSPEC-257 can't use automated TEMaterialGet functor as we need two possible defaults for diffuse alpha mode based on the alpha content of the diffuse texture

NORSPEC-222 fix issues with removing the use texture item selecting weave when the TE was BUMPY_TEXTURE, but no normal map was applied

NORSPEC-251 fix issues with not binning objects changed from having a material to using legacy bumps causing incorrect rendering

NORSPEC-247 Fix for rigged attachments with alpha masking on occluding alpha object when 100% transparent.