instead of trying to checkout viewer-build-util (which doesn't work) and then
reference action subdirs from the filesystem.

Also engage (initial placeholder) actions to sign and package the
platform-specific application artifacts.

instead of having it implied by specifying the containing directory.

instead of distinct viewer-post-bugsplat-{windows,mac} repos.

In a Windows build tree, we don't actually have an app-named top directory, so
don't package its containing directory -- just the app dir itself, e.g.
"newview/Release".

In a Mac build tree, though we do have "Second Life Mumble.app", its parent
directory also contains other large stuff. Try posting a temp directory
containing a symlink to the .app.

Ditch the "!*.bat" exclusion: the presence of a second path (even an
exclusion) changes how upload-artifact nests its contents.

This unblocks ReleaseOS builds, and also preps for SL-19242.

Streamline build.sh's Uploads section.

Previously we posted Windows-exe, macOS-exe artifacts that were a little
inconsistent: Windows-exe contained just the Windows executable, whereas
macOS-exe contained the whole .app tree (but without the .app directory).

Change to post Windows-app, macOS-app artifacts that each contain the whole
viewer install image, including the top-level application name directory. This
is what we'll need to codesign and notarize.

Move hexdump() and hexmix() stream formatters to new hexdump.h for potential
use by other tests.

In toPythonUsing() helper function, add a temp file to receive Python script
debug output, and direct debug output to that file. On test failure, dump the
contents of that file to the log.

Give NamedTempFile::peep() an optional target std::ostream; refactor
implementation as peep_via() that accepts a callable to process each text
line. Add operator<<() to stream the contents of a NamedTempFile object to
ostream -- but don't use that with LL_DEBUGS(), as it flattens the file
contents into a single log line. Instead add peep_log(), which streams each
individual text line to LL_DEBUGS().

(cherry picked from commit fd73b6e5)

This reverts commit 6cb906c4.

This reverts commit 46bd102e.

LLAudioEngine added a new abstract virtual method that wasn't yet implemented
for LLStreamingAudio_OpenAL.

Eliminate references to (no longer set) matrix.addrsize.

We want to run on a GitHub-hosted runner rather than one of our own.

because it moves the xcarchive.zip file away from where we later want to post
it to GitHub.

in the path passed as the macOS viewer_exe GitHub output.

On Mac, in the CMake USE_BUGSPLAT logic, we created both xcarchive.zip (which
is what BugSplat wants to see) and secondlife-symbols-darwin -64.tar.bz2 (which
we don't think is used for anything). The tarball was posted to codeticket --
but why? If the point is to manually re-upload to BugSplat in case of failure,
we'll do better saving xcarchive.zip to codeticket.

For SL-19243, posting xcarchive.zip directly supports the goal of breaking out
the upload to BugSplat as a separate step.

Anyway, since xcarchive.zip is a superset of the tarball, the tarball can be
recreated from the zip file, whereas the zip file can't be recreated from the
tarball without opening the .dmg installer and extracting the viewer executable.

If the xcarchive.zip file exists (that is, on Mac), post that to codeticket or
GitHub, as applicable, instead of the tarball. In fact, in the USE_BUGSPLAT
case, don't even bother creating the tarball since we're going to ignore it.

Make the new build.sh logic that insists on BUGSPLAT_USER and BUGSPLAT_PASS
conditional on BUGSPLAT_DB.

upload-mac-symbols.sh actually moves the xcarchive.zip file to /tmp, which is
why we couldn't find it when trying to list its contents after the upload.

The initial viewer-post-bugsplat-mac is just a placeholder so far, but we can
flesh it out while the viewer builds necessitated by this change are running,
and then we can iterate on viewer-post-bugsplat-mac without having to rebuild
the viewer.