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.

cmd/rogue/main.go

@@ -128,6 +128,7 @@ func chooseSeed(wizard bool) int32 {
 
 	// The C game computed `lowtime + getpid()` in int; the truncation to
 	// 32 bits is the same wraparound the C int arithmetic performed.
+	//nolint:mnd // C-faithful: the C int wraparound mask
 	return int32(time.Now().Unix()&0x7fffffff) +
 		int32(os.Getpid()&0x7fffffff)
 }