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/fight_test.go

@@ -1,3 +1,4 @@
+//nolint:testpackage // white-box tests reach unexported state (approved 2026-07-07)
 package game
 
 import "testing"
@@ -25,6 +26,8 @@ func spawnAdjacent(g *RogueGame, typ byte) *Monster {
 }
 
 func TestRollEmParsesMultiAttackDice(t *testing.T) {
+	t.Parallel()
+
 	g := mkGame(t, 42)
 	att := &Creature{Stats: Stats{Str: 16, Lvl: 20, Dmg: dice("1x4/1x4/1x4")}}
 	def := &Creature{Stats: Stats{ArmorClass: 10, HP: 1000}}
@@ -43,6 +46,8 @@ func TestRollEmParsesMultiAttackDice(t *testing.T) {
 }
 
 func TestFightKillsMonster(t *testing.T) {
+	t.Parallel()
+
 	g := mkGame(t, 7)
 	tp := spawnAdjacent(g, 'B') // bat: 1 hit die
 	tp.Stats.HP = 1
@@ -64,6 +69,8 @@ func TestFightKillsMonster(t *testing.T) {
 }
 
 func TestAttackHurtsPlayer(t *testing.T) {
+	t.Parallel()
+
 	g := mkGame(t, 9)
 	tp := spawnAdjacent(g, 'T') // troll: 1x8/1x8/2x6
 	tp.Stats.Lvl = 20           // always hits
@@ -80,6 +87,8 @@ func TestAttackHurtsPlayer(t *testing.T) {
 }
 
 func TestRunnersChaseHero(t *testing.T) {
+	t.Parallel()
+
 	g := mkGame(t, 3)
 	// Place a hobgoblin a few squares away in the hero's room and set it
 	// running at the hero.
@@ -104,6 +113,8 @@ func TestRunnersChaseHero(t *testing.T) {
 }
 
 func TestKilledLeprechaunDropsGoldViaFall(t *testing.T) {
+	t.Parallel()
+
 	g := mkGame(t, 21)
 	tp := spawnAdjacent(g, 'L')
 	tp.Stats.HP = 0