feat: add password creation step to onboarding wizard (#2)

- Add GET /api/security/password-is-default endpoint in server.py
- Add Step 2 (Create Your Password) to onboarding wizard HTML
- Renumber old steps: Domains→3, Ports→4, Complete→5
- Add 5th step dot indicator
- Update onboarding.js: TOTAL_STEPS=5, ROLE_SKIP_STEPS=[3,4] for desktop/node
- Add loadStep2/saveStep2 for password step with smart default detection
- Rename old step functions to loadStep3/saveStep3/loadStep4
- Add password form CSS styles in onboarding.css

Agent-Logs-Url: https://github.com/naturallaw777/staging_alpha/sessions/74a30916-fb2d-4f1d-9763-e380b1aa5540

Co-authored-by: naturallaw777 <99053422+naturallaw777@users.noreply.github.com>

app/sovran_systemsos_web/static/css/onboarding.css

@@ -575,6 +575,110 @@
   color: var(--text-secondary);
 }
 
+/* ── Password step (Step 2) ─────────────────────────────────────── */
+
+.onboarding-password-group {
+  display: flex;
+  flex-direction: column;
+  gap: 6px;
+  padding: 10px 0;
+}
+
+.onboarding-password-input-wrap {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+}
+
+.onboarding-password-input {
+  flex: 1;
+  padding: 9px 12px;
+  border: 1px solid var(--border-color);
+  border-radius: var(--radius-btn);
+  background-color: var(--card-color);
+  color: var(--text-primary);
+  font-size: 0.88rem;
+  font-family: 'Cantarell', 'Inter', 'Segoe UI', sans-serif;
+  transition: border-color 0.15s;
+}
+
+.onboarding-password-input:focus {
+  outline: none;
+  border-color: var(--accent-color);
+}
+
+.onboarding-password-toggle {
+  padding: 6px 10px;
+  background-color: var(--card-color);
+  border: 1px solid var(--border-color);
+  border-radius: var(--radius-btn);
+  color: var(--text-secondary);
+  cursor: pointer;
+  font-size: 1rem;
+  line-height: 1;
+  transition: background-color 0.15s, border-color 0.15s;
+  flex-shrink: 0;
+}
+
+.onboarding-password-toggle:hover {
+  background-color: rgba(137, 180, 250, 0.12);
+  border-color: var(--accent-color);
+}
+
+.onboarding-password-hint {
+  font-size: 0.78rem;
+  color: var(--text-dim);
+  line-height: 1.4;
+}
+
+.onboarding-password-warning {
+  padding: 10px 14px;
+  background-color: rgba(229, 165, 10, 0.1);
+  border: 1px solid rgba(229, 165, 10, 0.35);
+  border-radius: 8px;
+  font-size: 0.85rem;
+  color: var(--yellow);
+  line-height: 1.5;
+  margin-top: 6px;
+}
+
+.onboarding-password-success {
+  padding: 12px 16px;
+  background-color: rgba(166, 227, 161, 0.1);
+  border: 1px solid rgba(166, 227, 161, 0.35);
+  border-radius: 8px;
+  font-size: 0.92rem;
+  color: var(--green);
+  line-height: 1.5;
+}
+
+.onboarding-password-optional {
+  margin-top: 12px;
+  font-size: 0.88rem;
+}
+
+.onboarding-password-optional > summary {
+  cursor: pointer;
+  font-size: 0.85rem;
+  font-weight: 600;
+  color: var(--accent-color);
+  list-style: none;
+  user-select: none;
+}
+
+.onboarding-password-optional > summary::-webkit-details-marker {
+  display: none;
+}
+
+.onboarding-password-optional > summary::before {
+  content: '▶ ';
+  font-size: 0.65em;
+}
+
+.onboarding-password-optional[open] > summary::before {
+  content: '▼ ';
+}
+
 /* ── Reboot overlay ─────────────────────────────────────────────── */
 
 .reboot-overlay {