LearnSpace: full-stack educational whiteboard platform

Node.js/Express backend + vanilla JS frontend.
Features: real-time collaborative whiteboard (SSE), multi-page support,
LaTeX formulas, shapes/connectors, coordinate systems, number lines,
compass, zoom/pan, Catmull-Rom pencil smoothing, ruler/protractor with
rotation & resize controls, minimap navigation overlay, auto-measurements,
multi-page thumbnails sidebar, PNG export, page templates.
Student/teacher workflows: classes, assignments, library, dashboard.
Mobile responsive. SQLite (better-sqlite3).

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

backend/src/controllers/settingsController.js

@@ -0,0 +1,32 @@
+const db = require('../db/db');
+
+/* ── GET /api/settings/sims ─────────────────────────────────────────────── */
+function getSimSettings(req, res) {
+  const rows = db.prepare(`SELECT key, value FROM app_settings WHERE key IN ('sim_module_disabled','sim_disabled_ids')`).all();
+  const map = Object.fromEntries(rows.map(r => [r.key, r.value]));
+  res.json({
+    module_disabled: map['sim_module_disabled'] === '1',
+    disabled_ids: JSON.parse(map['sim_disabled_ids'] || '[]'),
+  });
+}
+
+/* ── PUT /api/settings/sims ─────────────────────────────────────────────── */
+function updateSimSettings(req, res) {
+  const { module_disabled, disabled_ids } = req.body;
+
+  if (module_disabled !== undefined) {
+    db.prepare(`INSERT INTO app_settings (key, value) VALUES ('sim_module_disabled', ?)
+                ON CONFLICT(key) DO UPDATE SET value = excluded.value`)
+      .run(module_disabled ? '1' : '0');
+  }
+
+  if (Array.isArray(disabled_ids)) {
+    db.prepare(`INSERT INTO app_settings (key, value) VALUES ('sim_disabled_ids', ?)
+                ON CONFLICT(key) DO UPDATE SET value = excluded.value`)
+      .run(JSON.stringify(disabled_ids));
+  }
+
+  res.json({ ok: true });
+}
+
+module.exports = { getSimSettings, updateSimSettings };