Widget order lab

@@ -21,9 +21,22 @@ What it exercises:  ## Two in a row, nothing between them +Both of these are on their own line, which is what the registry doc asks for,+but they are in one markdown paragraph because there is no blank line between+them. **Neither renders, and both leak to the reader as literal text.**+ ::adom-pinout{src="/ray/widget-order-lab/render/pinout-small.json" layout="dual"} ::adom-heatsink-via{src="/ray/widget-order-lab/render/heatsink.json"} +### The control: the same two tags, one blank line apart++If these two render, the rule is not "its own line" but "its own paragraph", and+the fix is either to match a tag inside a paragraph or to say so in the doc.++::adom-pinout{src="/ray/widget-order-lab/render/pinout-small.json" layout="dual"}++::adom-heatsink-via{src="/ray/widget-order-lab/render/heatsink.json"}+ ## Interleaved with prose  The paragraph before a widget should not merge into it, and the paragraph after