Add region picker for OpenSky default bounding box

Replace the free-text bounding-box field in the Web App OpenSky
settings with a grouped preset picker (World / Continents / Countries)
plus a Custom option that keeps the manual lamin,lomin,lamax,lomax
entry. Saved values that match a preset render as the friendly region
name, including in the locked/inherited display.

Change the API Server default bounding box to Europe to match the new
"Europe" preset.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Web App/web/src/components/Settings.vue

@@ -206,6 +206,68 @@ const OS_SCOPE_OPTS = [
   { value: 'org', label: 'Organization', icon: 'users' },
 ]
 
+// Predefined bounding boxes (lamin,lomin,lamax,lomax). The picker offers these
+// plus a "Custom…" option that reveals the free-text field for manual entry.
+// Europe is the default (kept in sync with the API Server's defaultBBox).
+const OS_BBOX_GROUPS = [
+  { label: 'World', options: [
+    { value: '-90,-180,90,180', label: 'World' },
+  ] },
+  { label: 'Continents', options: [
+    { value: '34,-25,72,45', label: 'Europe' },
+    { value: '-35,-18,38,52', label: 'Africa' },
+    { value: '5,25,82,180', label: 'Asia' },
+    { value: '7,-168,72,-52', label: 'North America' },
+    { value: '-56,-82,13,-34', label: 'South America' },
+    { value: '-48,110,-10,180', label: 'Oceania' },
+  ] },
+  { label: 'Countries', options: [
+    { value: '49,14.1,54.9,24.2', label: 'Poland' },
+    { value: '50.5,3.2,53.7,7.3', label: 'Netherlands' },
+    { value: '47.2,5.8,55.1,15.1', label: 'Germany' },
+    { value: '41.3,-5.2,51.1,9.6', label: 'France' },
+    { value: '49.9,-8.7,59,1.8', label: 'United Kingdom' },
+    { value: '35.9,-9.6,43.8,3.4', label: 'Spain' },
+    { value: '36.6,6.6,47.1,18.6', label: 'Italy' },
+    { value: '24,-125,49.5,-66.5', label: 'United States' },
+  ] },
+]
+const OS_BBOX_FLAT = OS_BBOX_GROUPS.flatMap((g) => g.options)
+
+// Normalise a bbox string to "n1,n2,n3,n4" so preset matching ignores spacing
+// and trailing-zero differences; returns '' when it isn't four valid numbers.
+function osNormBbox(s) {
+  const parts = String(s || '').split(',').map((x) => x.trim())
+  if (parts.length !== 4) return ''
+  const nums = parts.map(Number)
+  if (nums.some((n) => Number.isNaN(n))) return ''
+  return nums.join(',')
+}
+// Friendly label for a bbox value when it matches a preset (else '').
+function osBboxLabel(v) {
+  const norm = osNormBbox(v)
+  const m = norm && OS_BBOX_FLAT.find((o) => osNormBbox(o.value) === norm)
+  return m ? m.label : ''
+}
+
+// Manual-entry toggle: sticky once the user picks "Custom…", and implied when
+// the current value doesn't match any preset.
+const osBboxCustom = ref(false)
+const osBboxPreset = computed({
+  get() {
+    if (osBboxCustom.value) return '__custom__'
+    const norm = osNormBbox(osForm.bbox)
+    const match = norm && OS_BBOX_FLAT.find((o) => osNormBbox(o.value) === norm)
+    return match ? match.value : '__custom__'
+  },
+  set(v) {
+    if (v === '__custom__') { osBboxCustom.value = true; return }
+    osBboxCustom.value = false
+    osForm.bbox = v
+  },
+})
+const osBboxManual = computed(() => osBboxPreset.value === '__custom__')
+
 // Superadmin edits the global layer in the API panel — read-only in the Web App.
 const osReadOnly = computed(() => os.isSuperadmin)
 // The scope key currently in view (superadmin always sees the single read-only view).
@@ -233,6 +295,8 @@ function fillOsForm() {
   osForm.clientSecret = osField('clientSecret').own || ''
   osForm.plan = osField('plan').own || ''
   osForm.bbox = osField('bbox').own || ''
+  // Show the preset dropdown; the getter falls back to Custom for non-preset values.
+  osBboxCustom.value = false
 }
 
 function applyOpenSkyView(body) {
@@ -1433,14 +1497,22 @@ onBeforeUnmount(() => {
             </Row>
 
             <!-- bounding box -->
-            <Row title="Default bounding box" desc="lamin,lomin,lamax,lomax — used for live queries and the health probe." keywords="bounding box bbox area">
+            <Row title="Default bounding box" desc="Pick a region, or choose Custom to enter lamin,lomin,lamax,lomax by hand — used for live queries and the health probe." keywords="bounding box bbox area region country continent world europe custom coordinates">
               <template v-if="osLocked('bbox')">
                 <span class="inline-flex items-center gap-2 font-mono text-sm text-ink">
-                  {{ osField('bbox').effective || '—' }}
+                  {{ osBboxLabel(osField('bbox').effective) || osField('bbox').effective || '—' }}
                   <span v-if="osSourceLabel('bbox')" class="inline-flex items-center gap-1 rounded-full bg-surface-2 px-2 py-0.5 text-[10px] font-semibold text-ink-secondary"><Icon name="lock" :size="10" />{{ osSourceLabel('bbox') }}</span>
                 </span>
               </template>
-              <input v-else v-model="osForm.bbox" class="field w-64 font-mono" placeholder="50.5,3.2,53.7,7.3" />
+              <div v-else class="flex flex-col items-end gap-2">
+                <select v-model="osBboxPreset" class="field w-64">
+                  <optgroup v-for="g in OS_BBOX_GROUPS" :key="g.label" :label="g.label">
+                    <option v-for="o in g.options" :key="o.value" :value="o.value">{{ o.label }}</option>
+                  </optgroup>
+                  <option value="__custom__">Custom…</option>
+                </select>
+                <input v-if="osBboxManual" v-model="osForm.bbox" class="field w-64 font-mono" placeholder="50.5,3.2,53.7,7.3" />
+              </div>
             </Row>
 
             <!-- client id -->