Rename movement/world methods to idiomatic Go; remove all gotos

Refactor step 4. Renames (C breadcrumbs kept in doc comments):
doMove→moveHero, beTrapped→springTrap, rndmove→randomStep,
doRooms→digRooms, doPassages→digPassages, doMaze→digMaze,
chgStr→changeStrength, doRun→startRun, moveStuff→finishMove,
turnref→turnRefresh, moveMonst→moveMonster, doChase→chaseStep,
setOldch→setOldChar, cansee→canSee, roomin→roomIn, runto→runTo,
conn→connectRooms, putpass→putPassage, passnum→numberPassages,
numpass→numberPassage, rndPos→randomPos, rndRoom→randomRoom,
treasRoom→treasureRoom, accntMaze→accountMaze.

All goto/label flows are gone: moveHero uses a retry loop with the
PASSGO corner logic extracted into passageTurn; dispatch re-dispatches
via a loop; chaseStep re-checks via a loop; saveGame uses a labeled
prompt loop. Control flow and RNG call order are unchanged; suite
green.

game/sticks.go

@@ -80,7 +80,7 @@ func (g *RogueGame) doZap() {
 			case WandInvisibility:
 				tp.Flags.Set(Invisible)
 
-				if g.cansee(y, x) {
+				if g.canSee(y, x) {
 					g.mvaddch(y, x, tp.OldCh)
 				}
 			case WandPolymorph:
@@ -186,7 +186,7 @@ func (g *RogueGame) doZap() {
 
 			g.Delta.Y = y
 			g.Delta.X = x
-			g.runto(g.Delta)
+			g.runTo(g.Delta)
 		}
 	case WandLightning, WandFire, WandCold:
 		var name string
@@ -243,7 +243,7 @@ func (g *RogueGame) drain() {
 		if mp.Stats.HP -= cnt; mp.Stats.HP <= 0 {
 			g.killed(mp, g.seeMonst(mp))
 		} else {
-			g.runto(mp.Pos)
+			g.runTo(mp.Pos)
 		}
 	}
 }
@@ -339,7 +339,7 @@ func (g *RogueGame) fireBolt(start Coord, dir *Coord, name string) {
 				}
 			} else if ch != 'M' || tp.Disguise == 'M' {
 				if fromHero {
-					g.runto(pos)
+					g.runTo(pos)
 				}
 
 				if g.Options.Terse {