fix: add upgrade success messaging

chore: remove ARC52 mention

A string field was quoted only when it held a space or an equals sign,
so a value carrying a newline and neither was written out raw and split
one entry over two lines, which is exactly what Render promises not to
do and what makes the output greppable.

Nothing algod writes reaches this today: a stack trace goes into the
message, where collapseNewlines handles it, and the one structurally
multi-line field is built by a telemetry hook on a copy of the entry
that never reaches the file. The guarantee is Render's own, though, and
--file points the command at whatever file the user names, so the test
now covers control characters, quotes and backslashes alike -- %q
escapes them together and the guarantee stops depending on the producer.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PqPSx1wqM8rMdo4EHPa4jy

reportEmptyLogResult counted the sources the scan opened, which is the
list after PruneSources has already run. A --since newer than every
archive collapsed that count to the live log alone, so an empty live log
reported "the log file is empty, the node has not logged anything yet"
against a node with a year of rotated history behind it -- and sent the
user off to *start* a node that was already running.

The count is now the unpruned history, which leaves LogsNoMatchMsg to
explain the result. That is also the true answer: an archive pruned for
predating --since held nothing the search wanted either.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PqPSx1wqM8rMdo4EHPa4jy