Rename constructor to game.New(game.Params) per styleguide

NewGame(Config) becomes New(Params), and Restore takes Params too, so
the package's primary type gets the canonical New() constructor with a
named-field Params struct (styleguide points 139, 159). cmd/rogue and
all tests updated; ARCHITECTURE.md constructor references corrected.
Pure rename, suite green.

game/run_test.go

@@ -10,7 +10,7 @@ import (
 func TestRunScriptedSession(t *testing.T) {
 	tt := &testTerm{input: []byte("hjkl.i Qy")}
 
-	g := NewGame(Config{Seed: 99, Term: tt})
+	g := New(Params{Seed: 99, Term: tt})
 
 	err := g.Run()
 	if err != nil {
@@ -52,7 +52,7 @@ func TestRunManyTurns(t *testing.T) {
 	script = append(script, " Q y Qy"...)
 	tt := &testTerm{input: script}
 
-	g := NewGame(Config{Seed: 31337, Term: tt})
+	g := New(Params{Seed: 31337, Term: tt})
 
 	err := g.Run()
 	if err != nil {
@@ -68,7 +68,7 @@ func TestRunManyTurns(t *testing.T) {
 // wizard style, then descends and keeps playing.
 func TestRunDownStairs(t *testing.T) {
 	tt := &testTerm{input: []byte(">..Qy")}
-	g := NewGame(Config{Seed: 7, Term: tt})
+	g := New(Params{Seed: 7, Term: tt})
 	g.NewLevel()
 	g.Player.Pos = g.Level.Stairs // stand on the stairs
 	g.restored = true             // keep Run from regenerating the level
@@ -99,7 +99,7 @@ func TestSaveCommandRoundTrip(t *testing.T) {
 	// 'S' with no default file name goes straight to the name prompt.
 	script := "S" + path + "\n"
 	tt := &testTerm{input: []byte(script)}
-	g := NewGame(Config{Seed: 55, Term: tt})
+	g := New(Params{Seed: 55, Term: tt})
 
 	g.FileName = "" // force the name prompt
 
@@ -108,7 +108,7 @@ func TestSaveCommandRoundTrip(t *testing.T) {
 		t.Fatalf("Run: %v", runErr)
 	}
 
-	h, err := Restore(path, Config{Term: &testTerm{}})
+	h, err := Restore(path, Params{Term: &testTerm{}})
 	if err != nil {
 		t.Fatalf("Restore: %v", err)
 	}