Theme API: the display preference scheme (manual | auto) follows the account; seasons say their light half (#326)

ddiff --git a/server/themes/routes.js b/server/themes/routes.js
iindex 9fdf0d75..38b9156f 100644
---- a/server/themes/routes.js
++++ b/server/themes/routes.js
@@@ -91,18 +91,19 @@ router.get('/', async (req, res) => {
  });
  
  // ── Seasons: which theme stands in for the default theme when (openvibe-shared builtin-themes SEASONS) ──
--// GET /api/themes/seasons[?date=YYYY-MM-DD] → { seasons: [{ id, name, theme, from, to }], now: { id, name, theme } | null }
++// GET /api/themes/seasons[?date=YYYY-MM-DD] → { seasons: [{ id, name, theme, light?, from, to }], now: { id, name, theme, light? } | null }
++// (theme: the dark half; light: its light half, from openvibe-shared 4.12)
  // from/to are MM-DD, both days included, in the visitor's own calendar (the browser decides; `now` here is for the date
  // given, else today in UTC). Anyone on the default theme who has not turned seasonal themes off (display `seasonal`) sees
  // the season's theme, and every OpenVibe mark wears the season (theme-loader.js, ov-mark.js).
--function seasonList() { return (require('openvibe-shared/builtin-themes').SEASONS || []).map((s) => ({ id: s.id, name: s.name, theme: s.theme, from: s.from, to: s.to })); }
++function seasonList() { return (require('openvibe-shared/builtin-themes').SEASONS || []).map((s) => ({ id: s.id, name: s.name, theme: s.theme, ...(s.light ? { light: s.light } : {}), from: s.from, to: s.to })); }
  function seasonOn(md, list) { return list.find((s) => (s.from <= s.to ? md >= s.from && md <= s.to : md >= s.from || md <= s.to)) || null; }
  router.get('/seasons', (req, res) => {
      const list = seasonList();
      const asked = /^\d{4}-(\d{2})-(\d{2})$/.exec(String(req.query.date || ''));
      const md = asked ? `${asked[1]}-${asked[2]}` : new Date().toISOString().slice(5, 10);
      const now = seasonOn(md, list);
--    res.set('Cache-Control', 'public, max-age=3600').json({ seasons: list, now: now ? { id: now.id, name: now.name, theme: now.theme } : null });
++    res.set('Cache-Control', 'public, max-age=3600').json({ seasons: list, now: now ? { id: now.id, name: now.name, theme: now.theme, ...(now.light ? { light: now.light } : {}) } : null });
  });
  
  // ── Get User's Active Theme ──────────────────────────────────
@@@ -128,7 +129,9 @@ router.get('/me/active', (req, res, next) => {
  // ── Display preferences (motion, text size) — follow the account to every site ──
  // seasonal: the season's theme (openvibe-shared theme-loader Seasons: Pumpkin Night in October, Frost in December) in place
  // of the default theme, unless 'off' (the owner, 2026-10-24: "users can opt out … and just want their normal default").
--const DISPLAY = { motion: ['auto', 'reduced'], text: ['100', '112', '125'], seasonal: ['on', 'off'] };
++// scheme: 'manual' (the picked theme as it is) or 'auto' (its light or dark half, as the device is set; openvibe-shared
++// theme-loader Light / Dark / Auto, 2026-10-25).
++const DISPLAY = { motion: ['auto', 'reduced'], text: ['100', '112', '125'], seasonal: ['on', 'off'], scheme: ['manual', 'auto'] };
  function cleanDisplay(d) {
      if (!d || typeof d !== 'object') return null;
      const out = {};
ddiff --git a/test/themes-review.test.js b/test/themes-review.test.js
iindex 263ac175..38c52f04 100644
---- a/test/themes-review.test.js
++++ b/test/themes-review.test.js
@@@ -108,6 +108,9 @@ const token = async (id) => signToken(await db.prepare('SELECT * FROM users WHER
      assert.deepStrictEqual((await call('GET', '/api/themes/me/active', { as: 2 })).body.display, { motion: 'reduced', text: '112', seasonal: 'off' });
      r = await call('PUT', '/api/themes/me/display', { as: 2, body: { seasonal: 'maybe' } });
      assert.ok(!('seasonal' in (r.body.display || {})), 'only on or off');
++    r = await call('PUT', '/api/themes/me/display', { as: 2, body: { scheme: 'auto' } });
++    assert.strictEqual(r.body.display.scheme, 'auto', 'Auto (light or dark by the device) follows the account');
++    assert.strictEqual((await call('PUT', '/api/themes/me/display', { as: 2, body: { scheme: 'sepia' } })).body.display.scheme, undefined, 'only manual or auto');
  
      // ── Seasons: what stands in for the default theme when, for apps and the SDK ──
      r = await call('GET', '/api/themes/seasons?date=2026-10-25');