fix(scene): drop Z gate in fit_all so high-elevation entities show

Civil 3D files can legitimately carry profile geometry at huge Z
(10^6+ units) inside an otherwise small XY footprint — long-section
polylines on a road, for example. fit_all's outlier gate previously
filtered any point whose |x|, |y|, or |z| exceeded 10× the header
extent half-size, which dropped those polylines and made ZOOM
EXTENTS center on the main drawing only, leaving the profile
geometry permanently invisible.

The gate exists to reject origin-stuck entities and Ray/XLine far
points, both of which manifest as large XY excursions after
world_offset subtraction. Z-axis outliers are not a known garbage
pattern, so the gate now only checks XY.

Co-Authored-By: Claude Opus 4.7 <[email protected]>

src/scene/mod.rs

@@ -3274,16 +3274,18 @@ impl Scene {
 
         let mut min = glam::Vec3::splat(f32::MAX);
         let mut max = glam::Vec3::splat(f32::MIN);
-        // Reject points beyond 10× the drawing's EXTMIN→EXTMAX half-size.
-        // These come from origin-stuck entities (y ≈ -world_offset.y after subtraction),
-        // Ray/XLine far-points with bad direction vectors, or corrupt coordinates.
+        // Reject XY points beyond 10× the drawing's EXTMIN→EXTMAX half-size.
+        // These come from origin-stuck entities (y ≈ -world_offset.y after subtraction)
+        // or Ray/XLine far-points with bad direction vectors. The gate is XY-only:
+        // Civil 3D files can legitimately carry profile geometry at huge Z (10^6+
+        // units) inside an otherwise small XY footprint, and gating on Z hides them.
         let lim = self.local_extent_max;
         for wire in &wires {
             for &[x, y, z] in &wire.points {
                 if !x.is_finite() || !y.is_finite() || !z.is_finite() {
                     continue;
                 }
-                if x.abs() > lim || y.abs() > lim || z.abs() > lim {
+                if x.abs() > lim || y.abs() > lim {
                     continue;
                 }
                 min = min.min(glam::Vec3::new(x, y, z));