Libation's releases are ReadyToRun, so a Serilog reference resolves lazily
when the line holding it runs. An install folder whose Serilog.dll is missing
or older than the build therefore threw inside the very catch blocks that were
meant to report the problem, which destroyed the original exception and aborted
the in-app upgrade recovery before it could roll anything back.
Add StartupLog: a Serilog-free, never-throwing buffer for the window before
ConfigureLogging runs, replayed into Serilog once logging exists. Move the
pre-logging call sites onto it, including the crash-message and crash-dialog
paths that run precisely when the install is broken.
Those messages were silent before this change: Serilog.Log.Logger is still
Serilog's silent logger until App.RunMigrations. They now reach the log file.
Co-authored-by: rmcrackan <rmcrackan@gmail.com>
