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/wizard.go

@@ -1,8 +1,96 @@
 package game
 
 // wizard.c — special wizard commands, some of which are also non-wizard
-// commands under strange circumstances. The MASTER-only debug commands
-// (create_obj, show_map) arrive with the UI phase.
+// commands under strange circumstances. The DES password check is not
+// ported: wizard mode is enabled by configuration instead.
+
+// createObj is the wizard command for getting anything he wants (wizard.c
+// create_obj).
+func (g *RogueGame) createObj() {
+	obj := newObject()
+	g.msg("type of item: ")
+	obj.Type = g.readchar()
+	g.Msgs.Mpos = 0
+	g.msg("which %c do you want? (0-f)", obj.Type)
+	ch := g.readchar()
+	if isDigit(ch) {
+		obj.Which = int(ch - '0')
+	} else {
+		obj.Which = int(ch-'a') + 10
+	}
+	obj.Group = 0
+	obj.Count = 1
+	g.Msgs.Mpos = 0
+	switch {
+	case obj.Type == Weapon || obj.Type == Armor:
+		g.msg("blessing? (+,-,n)")
+		bless := g.readchar()
+		g.Msgs.Mpos = 0
+		if bless == '-' {
+			obj.Flags.Set(IsCursed)
+		}
+		if obj.Type == Weapon {
+			g.initWeapon(obj, obj.Which)
+			if bless == '-' {
+				obj.HPlus -= g.rnd(3) + 1
+			}
+			if bless == '+' {
+				obj.HPlus += g.rnd(3) + 1
+			}
+		} else {
+			obj.Arm = aClass[obj.Which]
+			if bless == '-' {
+				obj.Arm += g.rnd(3) + 1
+			}
+			if bless == '+' {
+				obj.Arm -= g.rnd(3) + 1
+			}
+		}
+	case obj.Type == Ring:
+		switch obj.Which {
+		case RProtect, RAddStr, RAddHit, RAddDam:
+			g.msg("blessing? (+,-,n)")
+			bless := g.readchar()
+			g.Msgs.Mpos = 0
+			if bless == '-' {
+				obj.Flags.Set(IsCursed)
+				obj.Arm = -1
+			} else {
+				obj.Arm = g.rnd(2) + 1
+			}
+		case RAggr, RTeleport:
+			obj.Flags.Set(IsCursed)
+		}
+	case obj.Type == Stick:
+		g.fixStick(obj)
+	case obj.Type == Gold:
+		g.msg("how much?")
+		buf := ""
+		if g.getStr(&buf, g.scr.Std) == Norm {
+			obj.SetGoldVal(cAtoi(buf))
+		}
+	}
+	g.addPack(obj, false)
+}
+
+// showMap prints out the whole map for the wizard (wizard.c show_map).
+func (g *RogueGame) showMap() {
+	hw := g.scr.Hw
+	hw.Clear()
+	for y := 1; y < NumLines-1; y++ {
+		for x := 0; x < NumCols; x++ {
+			real := g.Level.FlagsAt(y, x).Has(FReal)
+			if !real {
+				hw.Standout(true)
+			}
+			hw.MvAddCh(y, x, g.Level.Char(y, x))
+			if !real {
+				hw.Standout(false)
+			}
+		}
+	}
+	g.showWin("---More (level map)---")
+}
 
 // whatis identifies what a certain object is (wizard.c whatis).
 func (g *RogueGame) whatis(insist bool, typ int) {