go: port command loop, save/restore, tcell terminal, and the binary

- command.c in full: the command dispatcher with repeat counts, run
  prefixes, ctrl-run door-stop mode, fight-to-death targeting, and all
  wizard debug commands; search, help, identify, d_level/u_level, call,
  current
- main.c completed: Run()/playit() with the C double ROGUEOPTS parse;
  exit()-anywhere becomes a gameEnd panic recovered in Run
- save.c + state.c: gob SaveState snapshot with explicit pointer-to-
  index fixups for equipment, monster rooms, and chase targets (the
  rs_fix_thing role); save file deleted on restore as in C; SIGHUP/
  SIGTERM autosave hook
- wizard.c completed (create_obj, show_map), passages.c add_pass
- term/: tcell/v2 Terminal — the one third-party dependency — replacing
  curses and mdport's 900-line key decoder; shell escape via suspend
- cmd/rogue: flags -s/-d, SEED (wizard), ROGUEOPTS, ROGUE_WIZARD

Tests: full scripted sessions through Run (quit, descend stairs,
3200-move crash sweep, save-command round trip). Notable fixes found
by tests: gob silently drops embedded fields of unexported types, and
--More-- prompts swallow space-free input scripts.

game/save_test.go

@@ -0,0 +1,112 @@
+package game
+
+import (
+	"encoding/gob"
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestSaveRestoreRoundTrip(t *testing.T) {
+	g := mkGame(t, 4242)
+	// Dirty up some state so the round trip is meaningful.
+	g.Player.Purse = 123
+	g.Player.FoodLeft = 777
+	g.HasAmulet = true
+	g.Items.Potions[PHealing].Know = true
+	g.Items.Scrolls[SMap].Guess = "map???"
+	g.Monsters['F'-'A'].Stats.Dmg = "3x1" // mutated bestiary must survive
+	if len(g.Level.Monsters) > 0 {
+		g.Level.Monsters[0].Flags.Set(IsRun)
+		g.Level.Monsters[0].Dest = &g.Player.Pos
+	}
+
+	path := filepath.Join(t.TempDir(), "rogue.save")
+	if err := g.saveFile(path); err != nil {
+		t.Fatalf("saveFile: %v", err)
+	}
+
+	h, err := Restore(path, Config{Term: &testTerm{}})
+	if err != nil {
+		t.Fatalf("Restore: %v", err)
+	}
+
+	if _, err := os.Stat(path); !os.IsNotExist(err) {
+		t.Error("save file not deleted on restore (C anti-restart rule)")
+	}
+
+	if h.Player.Purse != 123 || h.Player.FoodLeft != 777 {
+		t.Errorf("player state lost: purse=%d food=%d",
+			h.Player.Purse, h.Player.FoodLeft)
+	}
+	if !h.HasAmulet {
+		t.Error("amulet flag lost")
+	}
+	if !h.Items.Potions[PHealing].Know {
+		t.Error("potion identification lost")
+	}
+	if h.Items.Scrolls[SMap].Guess != "map???" {
+		t.Error("scroll guess lost")
+	}
+	if h.Monsters['F'-'A'].Stats.Dmg != "3x1" {
+		t.Error("mutated bestiary lost")
+	}
+	if h.Rng.Seed != g.Rng.Seed {
+		t.Error("RNG state lost")
+	}
+	if renderMap(h) != renderMap(g) {
+		t.Error("restored level map differs")
+	}
+	if len(h.Level.Monsters) != len(g.Level.Monsters) {
+		t.Fatalf("monster count %d != %d",
+			len(h.Level.Monsters), len(g.Level.Monsters))
+	}
+	if len(g.Level.Monsters) > 0 {
+		m := h.Level.Monsters[0]
+		if m.Dest != &h.Player.Pos {
+			t.Error("monster chase target not re-aliased to the hero")
+		}
+		if h.Level.MonsterAt(m.Pos.Y, m.Pos.X) != m {
+			t.Error("map monster index not rebuilt")
+		}
+		if m.Room == nil {
+			t.Error("monster room pointer not rebuilt")
+		}
+	}
+	// Equipment aliasing: the wielded mace must be the same *Object as the
+	// one in the pack.
+	st := g.snapshot()
+	t.Logf("snapshot indices: weapon=%d armor=%d rings=%v packlen=%d",
+		st.Player.CurWeapon, st.Player.CurArmor, st.Player.CurRing,
+		len(st.Player.Body.Pack))
+	t.Logf("restored: CurWeapon=%p pack has %d items", h.Player.CurWeapon,
+		len(h.Player.Pack))
+	found := false
+	for i, o := range h.Player.Pack {
+		t.Logf("  pack[%d]=%p type=%c which=%d", i, o, o.Type, o.Which)
+		if o == h.Player.CurWeapon {
+			found = true
+		}
+	}
+	if !found {
+		t.Error("restored CurWeapon is not aliased into the pack")
+	}
+}
+
+func TestRestoreRejectsWrongVersion(t *testing.T) {
+	g := mkGame(t, 1)
+	path := filepath.Join(t.TempDir(), "rogue.save")
+	st := g.snapshot()
+	st.Version = "0.0.0"
+	f, err := os.Create(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := gob.NewEncoder(f).Encode(st); err != nil {
+		t.Fatal(err)
+	}
+	f.Close()
+	if _, err := Restore(path, Config{}); err == nil {
+		t.Error("restore accepted an out-of-date save")
+	}
+}