docs(hero): the detail is modelled inside the wall - that is why the facade renders plain

Measured the Y positions in the source and the imported mesh:

  blend scene Y        -12.50 .. +0.13
  Hero_Mass            y = -BODY_D/2 - 0.5, so it spans -12.50 .. -0.50
  Hero_Banner_1        -1.08 .. -1.02, i.e. 55 cm BEHIND the wall's front face
  imported bounds      y -13 .. +1250 cm

So the banners - and by the same construction the window bays and portal surrounds - sit inside the mass and
never render. The columns, cornice and dentils protrude, which is exactly what the captures show: a plain
block with six columns.

The camera check is answered as well: the three hero cameras are aimed at (-13336, 1307) where the hero actor
is, and the frontage sits at the origin, so the framing was correct all along.

Next step is mechanical, not artistic: put a FRONT_Y constant in Tools/hero_facade_build.py, place every
elevation detail relative to it, re-export and re-render. The model does not need remodelling before its
detail can be seen.

TODO.md

@@ -139,11 +139,27 @@ Reference: `security-game/docs/screens/refs/hollywood/el-capitan-facade-day-wiki
 
 So the model has the massing and most of the parts; what it lacks is **surface** (rustication, lettering, grille detail, balustrade) and material variation.
 
-**Before rebuilding anything, check the review shot.** The three hero captures show a plain block with six columns and nothing else - no banners, no windows, no portals - while the mesh demonstrably carries all four materials (`M_Facade_Banner`, `M_Facade_Stone`, `M_Facade_StoneShadow`, `M_Facade_GlassDark`) and is staged at `(-13336, 1307, 0)` with yaw 0. That suggests the cameras are framing the wrong actor (`Frontage_SM_ElCapitanTheatre` sits at the origin) or the wrong side, and the "rework" note may be describing a camera error rather than the model. Verify that first: one render with a camera aimed at `Hero_Facade` from Y -4000 at 8 m height.
+### Found: the detail is modelled inside the wall
+
+Measured, not guessed:
+
+```
+blend scene Y        -12.50 .. +0.13      (front of the wall at -0.50)
+Hero_Mass            y = -BODY_D/2 - 0.5  -> spans -12.50 .. -0.50
+Hero_Banner_1        y = -1.08 .. -1.02   -> 55 cm BEHIND the front face
+imported mesh bounds y = -13 .. +1250 cm
+```
+
+The facade's detail - banners, and by the same construction the window bays and portal surrounds - is placed **behind** the wall's front face, so it is inside `Hero_Mass` and never renders. That is why the captures show a plain block with six columns: the columns, cornice and dentils happen to protrude, everything else does not. The model does not need remodelling first; its detail needs moving in front of the wall.
+
+**Fix:** give `Tools/hero_facade_build.py` a `FRONT_Y = -BODY_D / 2.0 - 0.5` constant (the mass's front face) and place every elevation detail relative to it (`FRONT_Y - 0.10` for applied detail, `FRONT_Y` for flush), instead of the hand-typed negative coordinates each call site uses now. Then re-export, re-import and re-render.
+
+**And check the review shot.** The three hero captures show a plain block with six columns and nothing else - no banners, no windows, no portals - while the mesh demonstrably carries all four materials (`M_Facade_Banner`, `M_Facade_Stone`, `M_Facade_StoneShadow`, `M_Facade_GlassDark`) and is staged at `(-13336, 1307, 0)` with yaw 0. That suggests the cameras are framing the wrong actor (`Frontage_SM_ElCapitanTheatre` sits at the origin) or the wrong side, and the "rework" note may be describing a camera error rather than the model. Verify that first: one render with a camera aimed at `Hero_Facade` from Y -4000 at 8 m height.
 
 ### Tasks
 
-- [ ] Confirm the three hero captures frame `Hero_Facade` and not the frontage actor, then fix the cameras if they do not.
+- [x] Confirm the hero captures frame `Hero_Facade` - **done**: the cameras are aimed at (-13336, 1307), the hero actor is there, and the frontage is at the origin.
+- [ ] Move the elevation detail in front of the mass (`FRONT_Y` constant) and re-render - **do this first**, it explains the plain block.
 - [ ] Add surface detail the reference demands: rusticated banding, carved lettering on the motto band, window grilles, balustrade and finials on the parapet.
 - [ ] Rebuild the El Capitan hero facade to match the reference photography: cornice depth, the banner proportions, window rhythm, and the three entry portals.
 - [ ] Re-render the three ReviewMap staging shots and put them back in the status table for review.