feat: add AfterRun() hook

Fixes #288

hooks.go

@@ -3,17 +3,24 @@ package kong
 // BeforeResolve is a documentation-only interface describing hooks that run before resolvers are applied.
 type BeforeResolve interface {
 	// This is not the correct signature - see README for details.
-	BeforeResolve(args ...interface{}) error
+	BeforeResolve(args ...any) error
 }
 
 // BeforeApply is a documentation-only interface describing hooks that run before values are set.
 type BeforeApply interface {
 	// This is not the correct signature - see README for details.
-	BeforeApply(args ...interface{}) error
+	BeforeApply(args ...any) error
 }
 
 // AfterApply is a documentation-only interface describing hooks that run after values are set.
 type AfterApply interface {
 	// This is not the correct signature - see README for details.
-	AfterApply(args ...interface{}) error
+	AfterApply(args ...any) error
+}
+
+// AfterRun is a documentation-only interface describing hooks that run after Run() returns.
+type AfterRun interface {
+	// This is not the correct signature - see README for details.
+	// AfterRun is called after Run() returns.
+	AfterRun(args ...any) error
 }