SL-19674 Disable "Blinn-Phong" when a PBR material is applied to make it clear that those buttons are inoperable until you remove the PBR material.

SL-19709 Fix for fullbright shiny not factoring out exposure and flickering fullbright alpha.  Incidental decruft.

SL-19710 Fix for deadlock in LLPerfStats.  Move General thread initialization to earlier in session (unrelated).

SL-19236: Fix HUDs not rendering when transparent water graphics setting is off

SL-19656 Remove LLPerfStats thread and fold into General thread.  Hook avatar GPU time into LLPerfStats.  Incidental decruft.

SL-19690: Follow up on Rye Mutt's fix for shutdown crashes.

SL-19644: De-virtualize pushBatch

Rather than continuing to propagate try/catch (Closed)
(aka LLThreadSafeQueueInterrupt) constructs through the code base, make
WorkQueueBase::post() return bool indicating success (i.e. ! isClosed()).
This obviates postIfOpen(), which no one was using anyway.

In effect, postIfOpen() is renamed post(), bypassing the exception when
isClosed().

Review existing try/catch blocks of that sort, changing to test for post()
returning false.

Fix exceptions during shutdown causing early program termination

Fix LLThreadSafeQueueInterrupt in WorkQueueBase::postTo during shutdown by catching and returning false

Bump still uses its own pushBumpBatch function - OK, works the same as
before.

enable github actions mac nightly builds

DRTVWR-559: Replace debugLoggingEnabled() function with LL_DEBUGS().

Newer C++ compilers have different semantics around LLSDArray's special copy
constructor, which was essential to proper LLSD nesting. In short, we can no
longer trust LLSDArray to behave correctly. Now that we have variadic
functions, get rid of LLSDArray and replace every reference with llsd::array().

Fix SL-19675 crash due to thread unsafe LLRefCount usage possibly related to SL-19648

Cleanup with SL-19675 fix.  lifted empty check outside the workqueue post and cleaned up indentation