feat(onboarding): add one-shot bootstrap and first-run setup wizard (#285)

Adds a bootstrap launcher and a blocking first-run onboarding wizard that guides
new users through minimum Hermes setup from the browser UI.

Supported provider flows: OpenRouter, Anthropic, OpenAI, custom OpenAI-compatible.
OAuth/terminal-first flows remain via 'hermes model'.

Security hardening applied during review:
- /api/onboarding/setup restricted to loopback when auth disabled
- Newline injection guard in _write_env_file
- esc() on setup.unsupported_note in onboarding.js
- Test isolation fix (send_key instead of bot_name in contamination test)
- Skip markers for PyYAML-dependent tests in agent-less environments

Tests: 693 passed (up from 679)

Co-authored-by: Nathan Esquenazi <nesquena@gmail.com>
Co-authored-by: gabogabucho <gabogabucho@gmail.com>

tests/test_onboarding_static.py

@@ -0,0 +1,58 @@
+import pathlib
+
+
+REPO = pathlib.Path(__file__).parent.parent
+
+
+def read(path):
+    return (REPO / path).read_text(encoding="utf-8")
+
+
+def test_index_contains_onboarding_overlay_markup():
+    html = read("static/index.html")
+    assert 'id="onboardingOverlay"' in html
+    assert 'id="onboardingBody"' in html
+    assert 'id="onboardingNextBtn"' in html
+    assert 'src="/static/onboarding.js"' in html
+
+
+def test_onboarding_css_rules_exist():
+    css = read("static/style.css")
+    for selector in (
+        ".onboarding-overlay",
+        ".onboarding-card",
+        ".onboarding-step",
+        ".onboarding-status.warn",
+    ):
+        assert selector in css
+
+
+def test_onboarding_js_exposes_bootstrap_hooks():
+    js = read("static/onboarding.js")
+    assert "async function loadOnboardingWizard()" in js
+    assert "async function nextOnboardingStep()" in js
+    assert "api('/api/onboarding/status')" in js
+    assert "api('/api/onboarding/setup'" in js
+    assert "api('/api/onboarding/complete'" in js
+
+
+def test_onboarding_uses_i18n_helpers():
+    html = read("static/index.html")
+    js = read("static/onboarding.js")
+    i18n = read("static/i18n.js")
+    assert 'data-i18n="onboarding_title"' in html
+    assert 'data-i18n="onboarding_continue"' in html
+    assert "t('onboarding_step_system_title')" in js
+    assert "t('onboarding_step_setup_title')" in js
+    assert "t('onboarding_complete')" in js
+    assert "onboarding_title: 'Welcome to Hermes Web UI'" in i18n
+    assert "onboarding_title: 'Bienvenido a Hermes Web UI'" in i18n
+
+
+def test_bootstrap_script_contains_official_installer_and_windows_guard():
+    src = read("bootstrap.py")
+    assert (
+        "https://raw.githubusercontent.com/NousResearch/hermes-agent/main/scripts/install.sh"
+        in src
+    )
+    assert "Native Windows is not supported" in src