Adds p.mapleft, p.maptop to the SELECT and emits them as JSON values
(literal null when the columns are NULL). Consumed by the new
PrinterInstallerMap inno installer (feature/printer-map branch in
inno-installers) which renders the same Leaflet-style site map inside
a custom Inno wizard page rather than a browser, dodging the Edge
policy that blocks .bat downloads and unsigned .exe runs.
Additive change: existing consumers (PrinterInstaller.iss, tests,
installprinter.asp) read JSON by key name and ignore unknown fields.
SELECT change is additive too; no rs(0) numeric indexing in the
codebase. Schema-side: printers.mapleft, maptop already exist (they
are read by printerinstallermap.asp).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>