Rename constants to descriptive names (refactor step 1)

Pure rename, no behavior change; the full suite (RNG goldens,
generation invariants, scripted sessions, save round trip) is
unchanged and green.

- Creature flags: IsHuh→Confused, IsHalu→Hallucinating,
  CanHuh→CanConfuse, CanSee→CanSeeInvisible, IsRun→Awake,
  SeeMonst→SenseMonsters, IsCanc→Cancelled, IsLevit→Levitating,
  IsBlind/IsGreed/IsHaste/IsTarget/IsHeld/IsInvis/IsMean/IsRegen/
  IsFly/IsSlow → Blind/Greedy/Hasted/Targeted/Held/Invisible/Mean/
  Regenerates/Flying/Slowed, IsFound→Found
- Object flags: IsCursed→Cursed, IsKnow→Known, IsMissl→Missile,
  IsMany→Stackable, ObjIsFound→WasFound, IsProt→Protected
- Room flags: IsDark/IsGone/IsMaze → Dark/Gone/Maze; place flags:
  FPass→FPassage, FPNum→FPassNum, FTMask→FTrapMask
- Trap types: TDoor→TrapDoor ... TMyst→TrapMystery
- Item subtypes: P*→Potion* (PLSD→PotionLSD, PMFind→
  PotionDetectMonsters, ...), S*→Scroll* (SIDRorS→
  ScrollIdentifyRingOrStick, ...), R*→Ring* (RAddHit→RingDexterity,
  RNop→RingAdornment, ...), Ws*→Wand* (WsElect→WandLightning, ...),
  weapons (TwoSword→WeaponTwoHandedSword, Shiraken→WeaponShuriken,
  ...), armor (RingMail→ArmorRingMail, ...)
- Counts: Max{Potions,Scrolls,Rings,Sticks,Weapons,Armors} →
  Num{Potion,Scroll,Ring,Wand,Weapon,Armor}Types; NTraps→NumTrapTypes
- Level.NTraps field → TrapCount (also in the save snapshot)
- Original C constant names preserved as comment breadcrumbs in
  types.go so the lineage stays greppable

TODO.md: step 1 moved to Completed, step 2 (typed kinds) promoted to
Next Step.

game/wizard.go

@@ -27,7 +27,7 @@ func (g *RogueGame) createObj() {
 		bless := g.readchar()
 		g.Msgs.Mpos = 0
 		if bless == '-' {
-			obj.Flags.Set(IsCursed)
+			obj.Flags.Set(Cursed)
 		}
 		if obj.Type == Weapon {
 			g.initWeapon(obj, obj.Which)
@@ -48,18 +48,18 @@ func (g *RogueGame) createObj() {
 		}
 	case obj.Type == Ring:
 		switch obj.Which {
-		case RProtect, RAddStr, RAddHit, RAddDam:
+		case RingProtection, RingAddStrength, RingDexterity, RingIncreaseDamage:
 			g.msg("blessing? (+,-,n)")
 			bless := g.readchar()
 			g.Msgs.Mpos = 0
 			if bless == '-' {
-				obj.Flags.Set(IsCursed)
+				obj.Flags.Set(Cursed)
 				obj.Arm = -1
 			} else {
 				obj.Arm = g.rnd(2) + 1
 			}
-		case RAggr, RTeleport:
-			obj.Flags.Set(IsCursed)
+		case RingAggravateMonsters, RingTeleportation:
+			obj.Flags.Set(Cursed)
 		}
 	case obj.Type == Stick:
 		g.fixStick(obj)
@@ -131,7 +131,7 @@ func (g *RogueGame) whatis(insist bool, typ int) {
 	case Stick:
 		setKnow(obj, g.Items.Sticks[:])
 	case Weapon, Armor:
-		obj.Flags.Set(IsKnow)
+		obj.Flags.Set(Known)
 	case Ring:
 		setKnow(obj, g.Items.Rings[:])
 	}
@@ -142,7 +142,7 @@ func (g *RogueGame) whatis(insist bool, typ int) {
 // set_know).
 func setKnow(obj *Object, info []ObjInfo) {
 	info[obj.Which].Know = true
-	obj.Flags.Set(IsKnow)
+	obj.Flags.Set(Known)
 	info[obj.Which].Guess = ""
 }
 
@@ -187,8 +187,8 @@ func (g *RogueGame) teleport() {
 	g.mvaddch(p.Pos.Y, p.Pos.X, PlayerCh)
 	// turn off ISHELD in case teleportation was done while fighting a
 	// Flytrap
-	if p.On(IsHeld) {
-		p.Flags.Clear(IsHeld)
+	if p.On(Held) {
+		p.Flags.Clear(Held)
 		p.VfHit = 0
 		g.Monsters['F'-'A'].Stats.Dmg = "000x0"
 	}