Added documentation for the protocol package

protocol/doc.go

@@ -0,0 +1,19 @@
+// Package protocol contains functions for performing protocol detection.
+//
+// # Confidence scores
+//
+// All registered detectors in this package shall output a confidence score. If there are multiple
+// matching protocols, the protocol with the highest confidence score will be returned to the
+// caller.
+//
+// Confidence scores should be between 0 and 0.99, but there is no hard enforcement of this range
+// in this package.
+//
+// # Protocol matching
+//
+// The first level matching happens with  magic strings, as inspired by Go's [image.RegisterFormat]
+// function. The only addition that this package has made, is that you can also use the '*'
+// character for wildcard matching.
+//
+// The supported magic strings input is documented in the [Match] function.
+package protocol