chore(lint): adopt canonical golangci-lint config

Replace .golangci.yml with the shared canonical config. The old
config's top-level linters-settings block was silently ignored under
the v2 schema, so the lll/funlen/cyclop/dupl thresholds now actually
apply. The four repo-specific disables (mnd, exhaustive, paralleltest,
testpackage) move out of the config into targeted in-code nolint
directives carrying their original approval dates, keeping the config
byte-identical to the canonical one.

Fixes surfaced by the stricter settings: t.Parallel() added to all 32
tests, 24 overlong lines wrapped or their comments tightened, tcell
control-code returns rewritten as character literals, dupl markers on
the identically-shaped item data tables, and two wsl_v5 defer cuddles.

No behavior changes. The repo has no golangci-lint version pin (no
Dockerfile or CI; make lint runs the host binary, currently v2.12.2),
so there was nothing to bump.

game/creature.go

@@ -2,16 +2,18 @@ package game
 
 // Creature is the _t arm of the C THING union: the player or a monster.
 type Creature struct {
-	Pos      Coord  // position
-	Turn     bool   // if slowed, is it a turn to move
-	Type     byte   // what it is: 'A'..'Z' for monsters, '@' for the player
-	Disguise byte   // what mimic looks like
-	OldCh    byte   // character that was where it was
-	Dest     *Coord // where it is running to — aliases live coords (hero pos, room gold, another monster's pos)
-	Flags    CreatureFlags
-	Stats    Stats
-	Room     *Room     // current room for thing
-	Pack     []*Object // what the thing is carrying
+	Pos      Coord // position
+	Turn     bool  // if slowed, is it a turn to move
+	Type     byte  // what it is: 'A'..'Z' for monsters, '@' for the player
+	Disguise byte  // what mimic looks like
+	OldCh    byte  // character that was where it was
+	// Dest is where it is running to — aliases live coords (hero pos,
+	// room gold, another monster's pos).
+	Dest  *Coord
+	Flags CreatureFlags
+	Stats Stats
+	Room  *Room     // current room for thing
+	Pack  []*Object // what the thing is carrying
 }
 
 // Monster is a hostile creature on the level.