Actually ship the NWC feature, and guard against the drift that hid it

build.js swaps src/features/index.js for a generated module listing only the
features in its own ALL_FEATURES registry, so registering nwc in index.js
alone was not enough: its i18n strings shipped (they live elsewhere) but its
code never entered the bundle, and the settings card silently never rendered.

- add nwc to build.js ALL_FEATURES, after ark since it drives ark's headless
  pay/balance seam
- tools/feature-registry-check.js asserts the two lists agree on membership
  AND on construction order, since hook precedence depends on the order

Co-Authored-By: Claude Fable 5 <[email protected]>

2 files changed, 44 insertions, 2 deletions

diff --git a/build.js b/build.js
index 438f8bc..db07ed2 100644
--- a/build.js
+++ b/build.js
@@ -144,11 +144,13 @@ export async function buildSpWorker({ minify = true } = {}) {
 }
 
 // Optional-feature selection: HAL_FEATURES is a comma list of enabled
-// features (gifts,swaps,ark,zaps,sp). Unset means all; "none"/"" means a minimal
+// features (gifts,swaps,ark,zaps,sp,nwc). Unset means all; "none"/"" means a minimal
 // on-chain-only wallet. A build plugin swaps src/features/index.js for a
 // generated module that only imports the enabled features, so a disabled
 // feature's code (and its network endpoints) never enters the bundle.
-const ALL_FEATURES = { gifts: 'giftsFeature', swaps: 'swapsFeature', ark: 'arkFeature', zaps: 'zapsFeature', sp: 'spFeature', sync: 'syncFeature' };
+// NB order matters and must match src/features/index.js — nwc sits after ark
+// because it drives ark's headless pay/balance seam.
+const ALL_FEATURES = { gifts: 'giftsFeature', swaps: 'swapsFeature', ark: 'arkFeature', zaps: 'zapsFeature', sp: 'spFeature', nwc: 'nwcFeature', sync: 'syncFeature' };
 
 export function enabledFeatures(spec = process.env.HAL_FEATURES) {
   if (spec == null) return Object.keys(ALL_FEATURES);
diff --git a/tools/feature-registry-check.js b/tools/feature-registry-check.js
new file mode 100644
index 0000000..9b7ac5e
--- /dev/null
+++ b/tools/feature-registry-check.js
@@ -0,0 +1,40 @@
+// Guard: src/features/index.js and build.js's ALL_FEATURES must agree.
+// They drifted once (nwc was added to index.js only, so its i18n strings
+// shipped but its code never did — the settings card silently never rendered,
+// because build.js SWAPS OUT features/index.js for a generated module).
+//   bun tools/feature-registry-check.js
+import { readFileSync } from 'node:fs';
+
+const idx = readFileSync(new URL('../src/features/index.js', import.meta.url), 'utf8');
+const build = readFileSync(new URL('../build.js', import.meta.url), 'utf8');
+
+const inIndex = [...idx.matchAll(/import \{ (\w+Feature) \} from '\.\/([\w-]+)\.js'/g)]
+  .map((m) => ({ fn: m[1], name: m[2] }));
+const registry = build.match(/const ALL_FEATURES = \{([^}]*)\}/s)?.[1] || '';
+const inBuild = [...registry.matchAll(/(\w+):\s*'(\w+Feature)'/g)].map((m) => ({ name: m[1], fn: m[2] }));
+
+let ok = true;
+for (const f of inIndex) {
+  if (!inBuild.find((b) => b.fn === f.fn)) {
+    console.log(`x ${f.fn} (${f.name}.js) is in features/index.js but NOT in build.js ALL_FEATURES — it will not ship`);
+    ok = false;
+  }
+}
+for (const b of inBuild) {
+  if (!inIndex.find((f) => f.fn === b.fn)) {
+    console.log(`x ${b.fn} is in build.js ALL_FEATURES but not imported in features/index.js`);
+    ok = false;
+  }
+}
+// Compare the ORDER FEATURES ARE CONSTRUCTED IN (hook precedence depends on
+// it), not the order they happen to be imported in.
+const built = [...(idx.match(/return \[([^\]]*)\]/s)?.[1] || '')
+  .matchAll(/(\w+Feature)\(ctx\)/g)].map((m) => m[1]);
+const orderIdx = built.join(',');
+const orderBuild = inBuild.map((b) => b.fn).join(',');
+if (ok && orderIdx !== orderBuild) {
+  console.log(`x feature ORDER differs (hook precedence depends on it)\n  index.js: ${orderIdx}\n  build.js: ${orderBuild}`);
+  ok = false;
+}
+if (ok) console.log(`ok ${inIndex.length} features registered consistently`);
+process.exit(ok ? 0 : 1);