frontage: south block frontage, plus the placement bug it exposed

Adds the five remaining verified south-side buildings to the demo block
(6922, 6902, 6838 El Capitan Theatre, 6822 Budget, 6806-6820, 6800 Lee Drug),
exported in place from the OSM blockout by Tools/export_block_frontage.py,
imported to /Game/Hollywood/Frontage/ and staged by the demo builder with the
look material set (stone for the theatres, stucco for the retail run).

Adding neighbours exposed a pre-existing placement bug that was invisible while
the hero facade stood alone in an empty field:

- UE south is +Y here (south sidewalk Y +718..+1447), but the hero sat at
  Y -1450 on the NORTH side of the street.
- It was also at X -12024..-9420, 26 m east of the 6840 footprint; the frontage
  gap between 6902 and 6838 is X -14591..-12082.
- The two north-side buildings were on the SOUTH side, because their exporter
  mirrored Y.

Fixes: hero moved to X -13336 / Y +1307, inside its frontage gap; the frontage
and north-building exporters no longer apply a Y mirror (the FBX preset already
lands Blender -Y south on UE +Y south); player start and demo cameras moved to
the north sidewalk looking south; sun raised to pitch -62 so both frontages read
instead of the north side silhouetting.

Result: the demo is a street - continuous south frontage with the hero in it,
both sidewalks, the road with the designated crossing, and the north-side
buildings across the road.

Screenshots re-rendered and approved by the owner.

Squash of branch frontage-block-0.1.0 (PR #6).

Tools/ue_build_review_map.py

@@ -163,8 +163,10 @@ try:
     # from the north sidewalk, and the oblique street view from further west.
     # Hero placement in Unreal centimetres (see Geo/manifests/local-origin.md):
     # front plane on the building line, body behind it.
-    hero_x = -12024.5 + 1302.0
-    hero_y = -1450.0 + 7.0
+    # Corrected 2026-11-07 with the block frontage: UE south is +Y (south
+    # sidewalk Y +718..+1447) and 6840 occupies the frontage gap X -14591..-12082.
+    hero_x = -13336.0
+    hero_y = 1307.0
     hero = unreal.EditorAssetLibrary.load_asset("/Game/Hollywood/ElCapitan/SM_HeroFacade")
     # The imported mesh spans Y -7..+1250 cm in local space (front plane at -7, the
     # body behind it) and is centred on X, so the actor sits at building line + 7 cm.
@@ -274,12 +276,12 @@ try:
         demo_shots = [
             # 14 m back so the 14.5 m elevation fits: at 2 m the camera sees only
             # the colonnade's underside.
-            ("demo-spawn-view", unreal.Vector(-10722.5, -3500, 165), unreal.Vector(-10722.5, -1450, 700)),
+            ("demo-spawn-view", unreal.Vector(-13336, -3100, 420), unreal.Vector(-13336, 1300, 620)),
             # Street level, from the north sidewalk: the old camera sat at Y -400,
             # inside the facade body (which spans Y -1457..-200), so it looked at
             # the unlit back face. Y -2600 is on the sidewalk in front of the lit
             # elevation.
-            ("demo-street-level", unreal.Vector(-10850, -2600, 170), unreal.Vector(-10722.5, -1450, 400)),
+            ("demo-street-level", unreal.Vector(-13420, -1650, 170), unreal.Vector(-13336, 1300, 400)),
             # The designated mid-block crossing. Street arc length runs from the
             # west end (s=0 at X -27966 cm), so s=130.1 m is UE X -14956, not the
             # -24291 the old camera used (that is the s=36.6 crossing). Camera sits
@@ -288,7 +290,7 @@ try:
             ("demo-crossing", unreal.Vector(-15250, -2500, 400), unreal.Vector(-14956, 400, 150)),
             # the two north-side background buildings (TCL, Tussaud's) seen from
             # the south sidewalk, across Hollywood Blvd: their frontage and mass.
-            ("demo-north-buildings", unreal.Vector(-22800, -1000, 400), unreal.Vector(-22800, 3000, 300)),
+            ("demo-north-buildings", unreal.Vector(-22800, 2600, 420), unreal.Vector(-22800, -4200, 300)),
         ]
         seq = spawn(unreal.GigLineShotActor, unreal.Vector(0, 0, 300), "ShotSequencer")
         if seq: