The description for this PR says:

LoadSketch gRPC interface function now returns Sketch files in the root folder that have .json, .adoc or .md extension.

However, AFAICS this also returns such files in subdirectories. Is this intentional?

Also, what is the intended usecase here? To allow the user to edit/view adoc or md files when editing/viewing a sketch? How about json files? Is this intended for json data files in the sketch? Or forsketch.json? If the latter, should that maybe just that file be included and not all.json files (asking in relation to#1201, about breakage when acompilation_commands.json is present)?

This only affects the gRPC interface.

Is this really true? AFAICS it also causes these files to be copied into the build directory (or maybe that's a side effect of#1353?), which could influence the build, and can certainly influence performance.

Or for sketch.json?

It is handy forthedebug_custom.json file used to add support to the Arduino IDE 2.x debugger for non-CMSIS DAP compliant debuggers. The file must be added to the sketch.