fix(dx): update CLAUDE.md size gate, sync Makefile limit, add coverage tests

- CLAUDE.md: correct WASM raw size gate from 3 MB to 3.5 MB (matches size_test.go)
- CLAUDE.md: document error handling (log.E) and file I/O (coreio.Local) conventions
- Makefile: sync WASM_RAW_LIMIT to 3670016 (3.5 MB) to match size_test.go
- Tests: add coverage for NewContextWithService, Attr through wrapper nodes,
  Unless(true), and Text.Render with i18n service — core package 95.8% → 99.4%

No fmt.Errorf or os.ReadFile/os.WriteFile violations found.

Co-Authored-By: Virgil <virgil@lethean.io>

CLAUDE.md

@@ -27,7 +27,7 @@ See `docs/architecture.md` for full detail. Summary:
 - **Responsive**: Multi-variant breakpoint wrapper (`data-variant` attributes), renders all variants in insertion order
 - **Pipeline**: Render → StripTags → go-i18n/reversal Tokenise → GrammarImprint (server-side only)
 - **Codegen**: Web Component classes with closed Shadow DOM, generated at build time by `cmd/codegen/`
-- **WASM**: `cmd/wasm/` exports `renderToString()` only — size gate: < 3 MB raw, < 1 MB gzip
+- **WASM**: `cmd/wasm/` exports `renderToString()` only — size gate: < 3.5 MB raw, < 1 MB gzip
 
 ## Server/Client Split
 
@@ -53,6 +53,8 @@ Files guarded with `//go:build !js` are excluded from WASM:
 - Licence: EUPL-1.2 — add `// SPDX-Licence-Identifier: EUPL-1.2` to new files
 - Safe-by-default: HTML escaping via `html.EscapeString()` on Text nodes and attribute values, void element handling, entitlement deny-by-default
 - Deterministic output: sorted attributes on El nodes, reproducible block ID paths
+- Errors: use `log.E("scope", "message", err)` from `go-log`, never `fmt.Errorf`
+- File I/O: use `coreio.Local` from `go-io`, never `os.ReadFile`/`os.WriteFile`
 - Commits: conventional commits + `Co-Authored-By: Virgil <virgil@lethean.io>`
 
 ## Test Conventions

Makefile

@@ -1,8 +1,8 @@
 .PHONY: wasm test clean
 
 WASM_OUT := dist/go-html.wasm
-# Raw size limit: 3MB (Go WASM has ~2MB runtime floor)
-WASM_RAW_LIMIT := 3145728
+# Raw size limit: 3.5MB (Go 1.26 WASM runtime growth)
+WASM_RAW_LIMIT := 3670016
 # Gzip transfer size limit: 1MB (what users actually download)
 WASM_GZ_LIMIT := 1048576
 
@@ -21,9 +21,9 @@ $(WASM_OUT): $(shell find . -name '*.go' -not -path './dist/*')
 		echo "FAIL: gzip transfer size exceeds 1MB limit ($${GZ} bytes)"; \
 		exit 1; \
 	elif [ "$$RAW" -gt $(WASM_RAW_LIMIT) ]; then \
-		echo "WARNING: raw binary exceeds 3MB ($${RAW} bytes) — check imports"; \
+		echo "WARNING: raw binary exceeds 3.5MB ($${RAW} bytes) — check imports"; \
 	else \
-		echo "OK: gzip $${GZ} bytes (limit 1MB), raw $${RAW} bytes (limit 3MB)"; \
+		echo "OK: gzip $${GZ} bytes (limit 1MB), raw $${RAW} bytes (limit 3.5MB)"; \
 	fi
 
 clean:

node_test.go

@@ -3,6 +3,8 @@ package html
 import (
 	"strings"
 	"testing"
+
+	i18n "forge.lthn.ai/core/go-i18n"
 )
 
 func TestRawNode_Render(t *testing.T) {
@@ -191,6 +193,62 @@ func TestAttr_NonElement(t *testing.T) {
 	}
 }
 
+func TestUnlessNode_True(t *testing.T) {
+	ctx := NewContext()
+	node := Unless(func(*Context) bool { return true }, Raw("hidden"))
+	got := node.Render(ctx)
+	if got != "" {
+		t.Errorf("Unless(true) = %q, want %q", got, "")
+	}
+}
+
+func TestAttr_ThroughIfNode(t *testing.T) {
+	ctx := NewContext()
+	inner := El("div", Raw("content"))
+	node := If(func(*Context) bool { return true }, inner)
+	Attr(node, "class", "wrapped")
+	got := node.Render(ctx)
+	want := `<div class="wrapped">content</div>`
+	if got != want {
+		t.Errorf("Attr through If = %q, want %q", got, want)
+	}
+}
+
+func TestAttr_ThroughUnlessNode(t *testing.T) {
+	ctx := NewContext()
+	inner := El("div", Raw("content"))
+	node := Unless(func(*Context) bool { return false }, inner)
+	Attr(node, "id", "test")
+	got := node.Render(ctx)
+	want := `<div id="test">content</div>`
+	if got != want {
+		t.Errorf("Attr through Unless = %q, want %q", got, want)
+	}
+}
+
+func TestAttr_ThroughEntitledNode(t *testing.T) {
+	ctx := NewContext()
+	ctx.Entitlements = func(string) bool { return true }
+	inner := El("div", Raw("content"))
+	node := Entitled("feature", inner)
+	Attr(node, "data-feat", "on")
+	got := node.Render(ctx)
+	want := `<div data-feat="on">content</div>`
+	if got != want {
+		t.Errorf("Attr through Entitled = %q, want %q", got, want)
+	}
+}
+
+func TestTextNode_WithService(t *testing.T) {
+	svc, _ := i18n.New()
+	ctx := NewContextWithService(svc)
+	node := Text("hello")
+	got := node.Render(ctx)
+	if got != "hello" {
+		t.Errorf("Text with service context = %q, want %q", got, "hello")
+	}
+}
+
 func TestSwitchNode(t *testing.T) {
 	ctx := NewContext()
 	cases := map[string]Node{