fix(federation): anisotropic scene fill + centred key on mobile

- The fit now scales screen X and Y independently (capped at 1.75x
  anisotropy), so both 2D and 3D stretch to the container's aspect ratio —
  a portrait phone uses its full height instead of shrinking the orbit to
  the narrow width, and wide desktop panels spread horizontally.
- Legend/key centres at the top on mobile, mirroring the bottom-centre
  2D/3D toggle.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

neode-ui/src/components/federation/NetworkMap3D.vue

@@ -224,8 +224,10 @@ let ringsLayer: SVGGElement | null = null
 let width = 0
 let height = 0
 /** Scene scale + vertical centring — tweened alongside cam.tilt/persp during
- *  a 2D/3D toggle so the layout re-fits as it folds. */
-const fit = { unit: 1, centerY: 0 }
+ *  a 2D/3D toggle so the layout re-fits as it folds. unitX/unitY scale the
+ *  two screen axes independently (capped anisotropy) so the orbit fills the
+ *  container's aspect ratio instead of being bound by the narrow axis. */
+const fit = { unitX: 1, unitY: 1, centerY: 0 }
 let elapsed = 0
 let frame = 0
 let modeTween: gsap.core.Tween[] = []
@@ -328,8 +330,8 @@ function project(x: number, y: number, z: number) {
   const z2 = y * st + z1 * ct
   const s = cam.persp / (cam.persp + z2)
   return {
-    x: width / 2 + x1 * fit.unit * s * cam.zoom,
-    y: fit.centerY + y2 * fit.unit * s * cam.zoom,
+    x: width / 2 + x1 * fit.unitX * s * cam.zoom,
+    y: fit.centerY + y2 * fit.unitY * s * cam.zoom,
     s,
     z: z2,
   }
@@ -1056,7 +1058,7 @@ function onPointerUp(_e: PointerEvent) {
  *  scale to fill the container and centre vertically between the overlays.
  *  Pure with respect to tilt/persp so a mode toggle can compute its target
  *  fit and tween towards it. */
-function computeFit(tilt: number, perspVal: number): { unit: number; centerY: number } {
+function computeFit(tilt: number, perspVal: number): { unitX: number; unitY: number; centerY: number } {
   let maxRing = 1
   for (const r of ringPaths) maxRing = Math.max(maxRing, r.radius)
   // Requests hover loosely up to ~0.12 beyond their guide ring
@@ -1085,11 +1087,17 @@ function computeFit(tilt: number, perspVal: number): { unit: number; centerY: nu
   const marginTop = compact ? 42 : 54 // legend / toggle chips
   const marginBottom = compact ? 58 : 66 // hint + bottom-centre toggle (mobile)
   const bandH = Math.max(80, height - marginTop - marginBottom)
-  const unitX = (width / 2 - marginX) / maxAbsX
-  const unitY = bandH / Math.max(yMax - yMin, 0.001)
-  const u = Math.max(20, Math.min(unitX, unitY))
+  const rawX = (width / 2 - marginX) / maxAbsX
+  const rawY = bandH / Math.max(yMax - yMin, 0.001)
+  // Anisotropic fill: each axis takes its own bound, capped at 1.75× the
+  // other so the orbit stretches to the container's aspect ratio without
+  // degenerating. This is what lets a portrait phone use its full height in
+  // both 2D and 3D instead of shrinking to the narrow width.
+  const ANISO = 1.75
+  const unitX = Math.max(20, Math.min(rawX, rawY * ANISO))
+  const unitY = Math.max(20, Math.min(rawY, rawX * ANISO))
   // Place the projected ellipse's midpoint at the centre of the available band
-  return { unit: u, centerY: marginTop + bandH / 2 - ((yMax + yMin) / 2) * u }
+  return { unitX, unitY, centerY: marginTop + bandH / 2 - ((yMax + yMin) / 2) * unitY }
 }
 
 /** Re-fit after a graph change (e.g. the outermost orbit appeared/vanished).
@@ -1098,13 +1106,14 @@ function refit() {
   if (!modeInitialized) return
   const m = modeParams(viewMode.value)
   const target = computeFit(m.tilt, m.persp)
-  if (Math.abs(target.unit - fit.unit) < 0.5 && Math.abs(target.centerY - fit.centerY) < 0.5) return
+  if (Math.abs(target.unitX - fit.unitX) < 0.5
+    && Math.abs(target.unitY - fit.unitY) < 0.5
+    && Math.abs(target.centerY - fit.centerY) < 0.5) return
   gsap.killTweensOf(fit)
   if (introPlayed && !staticMode) {
     gsap.to(fit, { ...target, duration: 0.6, ease: motionTokens.ease.inOut })
   } else {
-    fit.unit = target.unit
-    fit.centerY = target.centerY
+    Object.assign(fit, target)
   }
 }
 
@@ -1123,8 +1132,7 @@ function applyMode(mode: MapMode, animate: boolean) {
   } else {
     cam.tilt = target.tilt
     cam.persp = target.persp
-    fit.unit = targetFit.unit
-    fit.centerY = targetFit.centerY
+    Object.assign(fit, targetFit)
     render()
   }
 }
@@ -1458,9 +1466,13 @@ onActivated(() => { if (built && !staticMode) attachTicker() })
 }
 
 @media (max-width: 767px) {
+  /* Key centred on mobile, mirroring the bottom-centre toggle */
   .node-map-legend {
     top: 8px;
-    left: 8px;
+    left: 50%;
+    transform: translateX(-50%);
+    width: max-content;
+    max-width: calc(100% - 16px);
     padding: 5px 10px;
     gap: 8px;
   }