feat: timeline refactor, docking UI, location/state dropdowns, sim_time cleanup

Templates:
- mission_timeline_preview: client-side rendering with lane stacking, wheel zoom,
  drag pan, percentage-based layout, event dedup, scale labels
- asset_detail: dock/undock modals with time selection, future event warning,
  Mission Label column replacing Location/State
- asset_entry_form: all_locations expanded to 72 items (draft board hierarchy),
  all_states dynamic from DB, event point dropdown uses same list
- Remove sim_time from all template url_for links
- base.html: remove Today button

JS:
- app.js: sim_time controls use POST /api/v1/sim-time API instead of URL param

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

app/static/app.js

@@ -0,0 +1,54 @@
+// ─── Sidebar ───
+function initSidebar() {
+  document.querySelectorAll('.ni[data-pg]').forEach(el => {
+    el.addEventListener('click', function(e) {
+      e.preventDefault();
+      window.location.href = this.getAttribute('href');
+    });
+  });
+  document.querySelectorAll('.nst').forEach(el => {
+    el.addEventListener('click', function() { this.classList.toggle('on'); });
+  });
+}
+initSidebar();
+
+// ─── Global Time Control ───
+function openTimeModal() {
+  const display = document.getElementById('sim-time-display');
+  if (!display) return;
+  const modal = document.getElementById('time-modal');
+  const input = document.getElementById('time-input');
+  if (modal && input) {
+    input.value = display.textContent.trim().replace(' ', 'T');
+    modal.classList.add('open');
+  }
+}
+function closeTimeModal() {
+  const modal = document.getElementById('time-modal');
+  if (modal) modal.classList.remove('open');
+}
+async function applyTime() {
+  const input = document.getElementById('time-input');
+  if (!input || !input.value) return;
+  await setSimTimeAndReload(input.value.replace('T', ' ') + ':00');
+}
+async function shiftTime(days) {
+  const display = document.getElementById('sim-time-display');
+  if (!display) return;
+  const d = new Date(display.textContent.trim().replace(' ', 'T') + 'Z');
+  d.setUTCDate(d.getUTCDate() + days);
+  await setSimTimeAndReload(d.toISOString().slice(0, 10) + ' 09:00');
+}
+async function resetTime() {
+  await setSimTimeAndReload('2060-03-12 09:00');
+}
+async function setSimTimeAndReload(timeStr) {
+  try {
+    await fetch('/api/v1/sim-time', {
+      method: 'POST',
+      headers: {'Content-Type': 'application/json'},
+      body: JSON.stringify({sim_time: timeStr})
+    });
+  } catch(e) {}
+  location.reload();
+}