Upstream rewrite of PRCXI9300Deck lost the Y-axis flip logic from the
original `(3-row)*96+13` formula. T1-T4 were rendered at the bottom
instead of the top. Reversed _DEFAULT_SITE_POSITIONS Y coordinates and
updated prcxi_9320_slim.json accordingly. Also added "plateadapter" and
"module" to slim JSON content_type entries.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>