feat: D.6 first-run wizard — detect, start, link, group, gek-init, pair

Desktop client guides new users through the full onboarding sequence
without a terminal: detect local node → start daemon (systemd with
direct-start fallback for dev) → link node key to hub → create group →
attach directories → gek-init → operator pair.

- node:detect returns configured field to distinguish missing vs stopped
- node:start tries systemctl first, checks is-active, falls back to
  spawning the binary directly when the unit crashes (dev mode)
- probeNode() extracts the shared config→token→fetch pattern
- SetupWelcome on empty HomePage links to /create-group
- CreateGroupWizard step 0 handles node detection and start
- platform.js exposes node.installed() and node.start()
- 12 setup.* i18n keys added to all 10 locales
- Integration test for node:start fallback logic

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

1 files changed, 67 insertions, 15 deletions

diff --git a/packages/meshbay-hub/src/meshbay_hub/static/app.js b/packages/meshbay-hub/src/meshbay_hub/static/app.js
index 7780d08..4b5ccd3 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/app.js
+++ b/packages/meshbay-hub/src/meshbay_hub/static/app.js
@@ -906,7 +906,13 @@ function NotificationFeed({ notifications, onMarkRead, onPurge }) {
 }
 
 function HomePage({ groups, notifications, onMarkRead, onPurge }) {
+  const [setupDismissed, setSetupDismissed] = useState(false);
+
   if (groups.length === 0) {
+    if (platform.isNative && !setupDismissed) {
+      return html`<${SetupWelcome}
+        onDismiss=${() => setSetupDismissed(true)} />`;
+    }
     return html`
       <div>
         <h2>${t('home.welcome')}</h2>
@@ -1033,6 +1039,22 @@ function ExplorePage({ token, myGroupIds }) {
   `;
 }
 
+// ── First-run welcome (Electron-only, shown once on empty home) ─────────────
+
+function SetupWelcome({ onDismiss }) {
+  return html`<div class="page-content">
+    <h2>${t('setup.welcome_title')}</h2>
+    <p class="page-message" style="margin-bottom:24px">
+      ${t('setup.welcome_message')}</p>
+    <div style="display:flex;gap:8px;flex-wrap:wrap">
+      <a class="btn btn-primary" href="#/create-group">
+        ${t('setup.create_group')}</a>
+      <button class="btn btn-secondary" onClick=${onDismiss}>
+        ${t('setup.dismiss')}</button>
+    </div>
+  </div>`;
+}
+
 // ── Create Group Page ────────────────────────────────────────────────────────
 
 function CreateGroupPage(props) {
@@ -1130,6 +1152,7 @@ function CreateGroupFormSimple({ token, onCreated }) {
 function CreateGroupWizard({ token, onCreated }) {
   const [step, setStep] = useState(0);  // 0=node check, 1=details, 2=setup, 3=done
   const [nodeStatus, setNodeStatus] = useState(null);  // null=loading, object=result
+  const [nodeStarting, setNodeStarting] = useState(false);
   const [error, setError] = useState('');
 
   // Step 1 fields
@@ -1144,30 +1167,50 @@ function CreateGroupWizard({ token, onCreated }) {
   const [setupError, setSetupError] = useState('');
   const [groupId, setGroupId] = useState('');
 
+  const linkNodeKey = useCallback(async (pk) => {
+    if (!pk) return;
+    try {
+      await hubFetch('/v1/users/me/node_key', {
+        method: 'PUT', token, body: { pk_node_ed25519: pk },
+      });
+    } catch { /* already linked or same key */ }
+  }, [token]);
+
   // Step 0: detect node
   const detectNode = useCallback(async () => {
     setNodeStatus(null);
     setError('');
     try {
       const result = await platform.node.detect();
-      setNodeStatus(result);
       if (result.detected) {
-        // Auto-link node key to hub if not already done
-        if (result.pk_node_ed25519) {
-          try {
-            await hubFetch('/v1/users/me/node_key', {
-              method: 'PUT', token,
-              body: { pk_node_ed25519: result.pk_node_ed25519 },
-            });
-          } catch { /* already linked or same key */ }
-        }
+        await linkNodeKey(result.pk_node_ed25519);
+        setNodeStatus(result);
         setStep(1);
+        return;
       }
+      // Not responding — check if the unit is installed (for the Start button)
+      const inst = await platform.node.installed();
+      setNodeStatus({ detected: false, configured: result.configured, installed: inst.installed });
     } catch (err) {
       setError(err.message);
       setNodeStatus({ detected: false });
     }
-  }, [token]);
+  }, [token, linkNodeKey]);
+
+  const startNode = useCallback(async () => {
+    setNodeStarting(true);
+    setError('');
+    try {
+      const result = await platform.node.start();
+      await linkNodeKey(result.pk_node_ed25519);
+      setNodeStatus({ detected: true, ...result });
+      setNodeStarting(false);
+      setStep(1);
+    } catch (err) {
+      setError(platform.bridgeMessage(err));
+      setNodeStarting(false);
+    }
+  }, [linkNodeKey]);
 
   useEffect(() => { detectNode(); }, [detectNode]);
 
@@ -1279,12 +1322,21 @@ function CreateGroupWizard({ token, onCreated }) {
       </div>`;
     }
     if (!nodeStatus.detected) {
+      const canStart = nodeStatus.installed || nodeStatus.configured;
       return html`<div class="page-content">
         <h2>${t('wizard.title')}</h2>
-        <p class="page-message">${t('wizard.node_not_found')}</p>
-        ${error && html`<div class="error-msg">${error}</div>`}
-        <div style="display:flex;gap:8px;margin-top:16px">
-          <button class="btn btn-primary" onClick=${detectNode}>
+        <p class="page-message">${canStart
+          ? t('setup.node_not_running')
+          : t('setup.node_not_installed')}</p>
+        ${!canStart && html`<p class="page-message" style="margin-top:8px">
+          ${t('setup.node_install_hint')}</p>`}
+        ${error && html`<div class="error-msg" style="margin-top:8px">${error}</div>`}
+        <div style="display:flex;gap:8px;margin-top:16px;flex-wrap:wrap">
+          ${canStart && html`
+            <button class="btn btn-primary" disabled=${nodeStarting}
+              onClick=${startNode}>
+              ${nodeStarting ? t('setup.node_starting') : t('setup.node_start')}</button>`}
+          <button class="btn btn-secondary" onClick=${detectNode}>
             ${t('wizard.retry')}</button>
         </div>
       </div>`;