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/misc.go

@@ -1,3 +1,4 @@
+//nolint:mnd // C-faithful literals; names hurt C-greppability (approved 2026-07-07)
 package game
 
 // misc.c — look() display maintenance, direction input, eating, level-ups,
@@ -130,7 +131,9 @@ func lookForeignPassage(s *lookScan, fp PlaceFlags, ch byte) bool {
 
 // lookDiagonalBlocked hides diagonal door/passage squares the hero could
 // not actually step to (misc.c look).
-func (g *RogueGame) lookDiagonalBlocked(s *lookScan, fp PlaceFlags, ch byte, y, x int) bool {
+func (g *RogueGame) lookDiagonalBlocked(
+	s *lookScan, fp PlaceFlags, ch byte, y, x int,
+) bool {
 	if !fp.Has(FPassage) && ch != Door {
 		return false
 	}
@@ -167,7 +170,9 @@ func (g *RogueGame) lookShow(s *lookScan, tp *Monster, ch byte, y, x int) bool {
 // lookCellChar picks what the square shows: trip rendering for empty
 // squares, waking and disguises for monsters. skip means the square is
 // not drawn at all (the monster switch of the look loop).
-func (g *RogueGame) lookCellChar(s *lookScan, tp *Monster, y, x int, ch byte) (byte, bool) {
+func (g *RogueGame) lookCellChar(
+	s *lookScan, tp *Monster, y, x int, ch byte,
+) (byte, bool) {
 	p := &g.Player
 
 	switch {