A ProBoardDef can declare builtInSdCsPin, and the store already built a FAT
card from the project files for it - but there was no way to put YOUR files
on that card: the upload panel only existed for the microsd-card component
and for parts with metadata.sdSlot, and boards have no properties bag.
Boards now carry sdFiles (same shape the SD panel persists everywhere else):
- BoardInstance.sdFiles, consumed by the store's Run path (card component
still wins when one is on the canvas);
- the board inspector shows the SD Card panel whenever the board kind
declares builtInSdCsPin, and routes the panel's onChange to updateBoard;
- .vlx round-trips it (serialisableBoard + payload type), and gallery
examples can pre-load the slot via ExampleBoard.sdFiles, applied by
loadExample the way the panel would.
First user: the XIAO ESP32S3 Sense (CS=GPIO21), whose board def and example
land in the pro overlay.
cfa03aeaf9