feat(web): Start Display on Boot toggle on the General tab

Turns ledmatrix.service's autostart on or off at once through the existing
enable_autostart / disable_autostart system actions (sudo grants already in
lib_sudoers.sh). The checkbox shows systemd's own state, read with
`systemctl is-enabled`, so nothing is stored in config.json and the default
stays on. Hidden when the state cannot be read; a refused change puts the
box back and shows the route's message.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

test/js/run_all.js

@@ -32,7 +32,8 @@ const UNIT = ['unit/test_list_filter.js', 'unit/test_render_cards.js',
               'unit/test_page_registry.js', 'unit/test_core_modules.js',
               'unit/test_overview_reconciliation_poll.js',
               'unit/test_display_partial_ids.js',
-              'unit/test_general_web_login_token.js'];
+              'unit/test_general_web_login_token.js',
+              'unit/test_general_display_autostart.js'];
 const DOM = ['dom/test_installed_dom.js', 'dom/test_store_dom.js', 'dom/test_no_double_fetch.js',
              'dom/test_tools_sections.js', 'dom/test_cache_page.js',
              'dom/test_durations_page.js', 'dom/test_operation_history_page.js',

test/js/unit/test_general_display_autostart.js

@@ -0,0 +1,77 @@
+// The General tab's "Start Display on Boot" checkbox (setDisplayAutostart in
+// static/v3/js/pages/general.js) posts enable_autostart / disable_autostart
+// to /api/v3/system/action and puts the box back when that is refused --
+// including the route's HTTP-200 {status: "error"} answer for a failed
+// systemctl (e.g. the sudo rule is missing).
+//
+// Fake fetch, no jsdom and no server needed.
+
+const path = require('path');
+const { pathToFileURL } = require('url');
+
+const JS = path.resolve(__dirname, '../../../web_interface/static/v3/js');
+const load = f => import(pathToFileURL(path.join(JS, f)).href);
+
+let pass = 0, fail = 0;
+const ok = (label, cond, extra) => cond
+  ? (pass++, console.log('  ok   ' + label))
+  : (fail++, console.log('  FAIL ' + label + (extra !== undefined ? '  ' + JSON.stringify(extra) : '')));
+
+async function run(checked, answer) {
+  const { createApi } = await load('core/api.js');
+  const general = await load('pages/general.js');
+  const sent = [];
+  const notes = [];
+  const fetch = (url, init) => {
+    sent.push([url, JSON.parse(init.body)]);
+    if (answer === 'network') return Promise.reject(new TypeError('Failed to fetch'));
+    return Promise.resolve({
+      ok: answer.ok, status: answer.ok ? 200 : 500,
+      headers: { get: () => null },
+      text: () => Promise.resolve(JSON.stringify(answer.body)),
+    });
+  };
+  const ctx = { root: {}, state: {}, signal: { aborted: false },
+                api: createApi({ fetch }), notify: (m, t) => notes.push([m, t]) };
+  const box = { checked, disabled: false };
+  await general.setDisplayAutostart(ctx, box);
+  return { box, sent, notes };
+}
+
+(async () => {
+  console.log('\n── General tab: Start Display on Boot ──');
+
+  {
+    const t = await run(false, { ok: true, body: { status: 'success', message: 'ok' } });
+    ok('unchecking posts disable_autostart',
+       t.sent.length === 1 && t.sent[0][0] === '/api/v3/system/action' && t.sent[0][1].action === 'disable_autostart', t.sent);
+    ok('...stays unchecked and re-enabled', t.box.checked === false && t.box.disabled === false);
+    ok('...and reports success', t.notes.some(([, type]) => type === 'success'), t.notes);
+  }
+
+  {
+    const t = await run(true, { ok: true, body: { status: 'success' } });
+    ok('checking posts enable_autostart', t.sent[0][1].action === 'enable_autostart', t.sent);
+  }
+
+  {
+    const t = await run(false, { ok: true, body: { status: 'error', message: 'sudo: a password is required' } });
+    ok('a failed systemctl (HTTP 200, status error) puts the box back', t.box.checked === true && !t.box.disabled);
+    ok('...and shows the route\'s message',
+       t.notes.some(([m, type]) => type === 'error' && /sudo/.test(m)), t.notes);
+  }
+
+  {
+    const t = await run(true, { ok: false, body: { status: 'error', message: 'boom' } });
+    ok('an HTTP error puts the box back', t.box.checked === false && !t.box.disabled);
+  }
+
+  {
+    const t = await run(true, 'network');
+    ok('a network failure puts the box back', t.box.checked === false && !t.box.disabled);
+    ok('...and reports it', t.notes.some(([, type]) => type === 'error'), t.notes);
+  }
+
+  console.log(`\n${pass} passed, ${fail} failed\n`);
+  process.exit(fail ? 1 : 0);
+})().catch(e => { console.log('HARNESS ERROR: ' + e.stack); process.exit(1); });

test/test_general_display_autostart.py

@@ -0,0 +1,60 @@
+"""The General tab's "Start Display on Boot" toggle reads systemd's state.
+
+ledmatrix.service enabled -> checked, disabled -> unchecked, unreadable (no
+systemctl, unit not installed) -> no toggle. The toggle itself posts the
+existing enable_autostart / disable_autostart system actions, whose sudo
+grants test_systemctl_sudoers_alignment.py already checks.
+"""
+import subprocess
+import sys
+from pathlib import Path
+
+import pytest
+
+PROJECT_ROOT = Path(__file__).parent.parent
+sys.path.insert(0, str(PROJECT_ROOT))
+
+from test.test_web_settings_ui import client  # noqa: F401,E402
+from web_interface.blueprints import pages_v3  # noqa: E402
+
+
+REAL_RUN = subprocess.run
+UNIT_QUERY = ['systemctl', 'is-enabled', 'ledmatrix.service']
+
+
+def _fake_systemctl(monkeypatch, answer):
+    """Answer the unit query with `answer` (stdout, or an exception to
+    raise); every other command (the update channel's git) runs for real."""
+    calls = []
+
+    def run(cmd, *args, **kwargs):
+        if cmd != UNIT_QUERY:
+            return REAL_RUN(cmd, *args, **kwargs)
+        calls.append(cmd)
+        if isinstance(answer, Exception):
+            raise answer
+        return subprocess.CompletedProcess(cmd, 0, stdout=answer, stderr='')
+    monkeypatch.setattr(pages_v3.subprocess, 'run', run)
+    return calls
+
+
+def _toggle(body):
+    start = body.find('data-action="display-autostart"')
+    return None if start < 0 else body[start:body.find('>', start)]
+
+
+@pytest.mark.parametrize('stdout, checked', [('enabled\n', True), ('disabled\n', False)])
+def test_toggle_reflects_the_unit(client, monkeypatch, stdout, checked):
+    calls = _fake_systemctl(monkeypatch, stdout)
+    tag = _toggle(client.get('/v3/partials/general').get_data(as_text=True))
+    assert calls == [UNIT_QUERY]
+    assert tag is not None
+    assert ('checked' in tag) is checked
+
+
+@pytest.mark.parametrize('outcome', [FileNotFoundError(), 'not-found\n'])
+def test_toggle_hidden_when_state_unreadable(client, monkeypatch, outcome):
+    _fake_systemctl(monkeypatch, outcome)
+    body = client.get('/v3/partials/general').get_data(as_text=True)
+    assert _toggle(body) is None
+    assert 'name="plugins_directory"' in body  # rest of the tab still renders