chore: retire check 31 (bn chrome sync) — chrome is host-only since P3

The cms↔pluginsdk bn-chrome byte-compare no longer applies: pluginsdk
deleted templates/bn at v0.2.0, so cms's copy is host-only and
authoritative. Remove check_templatesync.go, drop check 31 from the
registry-order test, and regenerate golden snapshots (34→33 checks).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

check_templatesync.go

@@ -1,67 +0,0 @@
-package main
-
-import (
-	"bytes"
-	"os"
-	"path/filepath"
-)
-
-// The bn chrome files authored in cms/backend/templates/bn and mechanically
-// synced (make sync-templates) into the sibling pluginsdk repo's templates/bn.
-// Guest-side plugin templates compile pluginsdk's copy into their wasm, so the
-// two checkouts must stay byte-identical. validation.go is intentionally NOT in
-// this set (cms's is a two-context-key bridge over the SDK tracker); neither
-// is img.templ (cms-only, not referenced by the chrome).
-// See cms docs/superpowers/specs/2026-07-07-bn-chrome-single-source-design.md.
-var templateSyncSet = []string{
-	"head.templ",
-	"toolbar.templ",
-	"engagement.templ",
-	"asset_hooks.go",
-}
-
-func init() {
-	register(Check{
-		Seq:   310,
-		ID:    "31",
-		Title: "bn chrome templates in sync between cms and pluginsdk",
-		Run: func(ctx *ScanContext, rep *Reporter) {
-			cmsDir := filepath.Join(ctx.repoRoot, "backend", "templates", "bn")
-			if _, err := os.Stat(cmsDir); err != nil {
-				rep.Skip("no backend/templates/bn in this repo — template-sync gate not applicable")
-				return
-			}
-			sdkDir := filepath.Join(ctx.repoRoot, "..", "pluginsdk", "templates", "bn")
-			if _, err := os.Stat(sdkDir); err != nil {
-				rep.Skip("sibling pluginsdk checkout not found — cannot verify template sync")
-				return
-			}
-
-			var drifted []string
-			for _, name := range templateSyncSet {
-				cmsBytes, err := os.ReadFile(filepath.Join(cmsDir, name))
-				if err != nil {
-					drifted = append(drifted, name+" (unreadable in cms: "+err.Error()+")")
-					continue
-				}
-				sdkBytes, err := os.ReadFile(filepath.Join(sdkDir, name))
-				if err != nil {
-					drifted = append(drifted, name+" (missing in pluginsdk)")
-					continue
-				}
-				if !bytes.Equal(cmsBytes, sdkBytes) {
-					drifted = append(drifted, name)
-				}
-			}
-
-			if len(drifted) > 0 {
-				rep.Fail("%d bn chrome file(s) drifted between cms and pluginsdk", len(drifted))
-				for _, name := range drifted {
-					rep.Findingf("templates/bn/%s differs — cms is the authoring source; run `make sync-templates` in cms, then commit + tag + push pluginsdk", name)
-				}
-			} else {
-				rep.OK("bn chrome sync set byte-identical across cms and pluginsdk (%d files)", len(templateSyncSet))
-			}
-		},
-	})
-}

registry_test.go

@@ -18,7 +18,7 @@ func TestRegistryOrder(t *testing.T) {
 		"1", "2", "2b", "2c", "2d", "2e", "2f", "3", "3b", "4",
 		"5", "6", "7", "8", "9", "10", "10b", "10disc", "11", "12",
 		"13", "14", "15", "16", "17", "18", "19", "20", "21", "22",
-		"28", "29", "30", "31",
+		"28", "29", "30",
 	}
 
 	ordered := make([]Check, len(registry))

testdata/golden/clean/expected.stdout

@@ -1,2 +1,2 @@
 check-safety FIXTURE_DIR
-34 checks: 20 ok 14 skip -> OK
+33 checks: 20 ok 13 skip -> OK

testdata/golden/nomod/expected.stdout

@@ -10,4 +10,4 @@ FAIL 15 1 err.Error() leak(s) to HTTP clients — log via slog.Error() and retur
 FAIL 17 1 TODO marker(s) found — ship explicit behavior, not placeholders
   internal/service/handler.go:14 // TODO: add proper initialisation
 
-34 checks: 14 ok 15 skip 5 fail -> FAIL
+33 checks: 14 ok 14 skip 5 fail -> FAIL