add sources, add visx to release flow

dsl/ast.go

@@ -9,6 +9,7 @@ type File struct {
 	BuildDarwin  string
 	Timeout      time.Duration
 	Binary       string // executable name produced by build (default: solution)
+	Sources      string // glob pattern for source files, expanded as $SOURCES in build
 
 	NormalizeCRLF  bool // strip \r before matching stdout/stderr/outFiles
 	TrimTrailingWS bool // trim trailing whitespace on each line before matching