fix(hero): pale marble-limestone stone at the reference's value, per the owner's note

The owner rejected the previous pass on three counts - too saturated, too dark, and the albedo was wrong for the
building. All three were true, and the reason the colour work kept missing is that the albedo never reached the
material: import_albedo() resolved the repository root one level short after the tools move, so every 'stone'
render was the flat tint alone. That is fixed first.

Then measured instead of guessed: the reference's sunlit stone samples sRGB ~0.49 (linear ~0.19), attic
highlight ~0.75, shaded recess ~0.43, and it is nearly neutral, not warm. New albedo generated for a pale
low-contrast marble-limestone ashlar (two checkpoints compared, AlbedoBase won) and the tint moved to
(0.47, 0.455, 0.43) with the shadow at (0.30, 0.29, 0.27), which lands lit stone around 0.62 sRGB - brighter
than the last pass and close to the photographs.

The elevation now reads as pale, low-saturation concrete/marble with thin-jointed ashlar. Row 4-6 re-rendered
and pending. The architectural pass the owner also asked for - carved inscription, medallions, banner lettering,
capital and grille depth - is untouched and recorded as the next step.

THIRD_PARTY_NOTICES carries the new seed and prompt.

THIRD_PARTY_NOTICES.md

@@ -51,4 +51,4 @@ Rules that still apply, because they are about shipped output rather than local
 | Terrain and street prototype | USGS 3DEP DEM, OSM data, project scripts | Public domain USGS data; OpenStreetMap data, local private use | Source manifests in `Geo/manifests/`. |
 | Hero façade blockout | Project-owned geometry from `Tools/blender/hero_facade_build.py`, dimensions from OSM and the reference photography | Project-owned | Committed with a per-part evidence report (`Art/blender/hero/hero-facade-*.json`) and a position sidecar (`hero-facade.geo.json`). |
 | Street props (candidate reuse) | Sibling project `…/06-games/security-game`, `assets/models/blender_src/*.blend` | Project-owned by the same author | **Not yet imported.** Sources copied to `Art/props/blender_src/` with `Art/props/reuse-manifest.json`; a licence statement is required before any of them ship. |
-| Hero façade stone albedo | `Art/textures/generated/T_FacadeAshlar_AI.png`, generated locally with ComfyUI (Stability Matrix, `/home/zwitschi/StabilityMatrix/Data/README.md`) using **AlbedoBase XL v3.1-Large** at seed 21, workflow `texture_albedobase_xl` | Civitai model 140737 — commercial image use allowed, credit required | [ ] credit line still to be added to the game's credits document before release; sidecar `T_FacadeAshlar_AI.json` records model, prompt, seed and graph |
+| Hero façade stone albedo | `Art/textures/generated/T_FacadeAshlar_AI.png`, generated locally with ComfyUI (Stability Matrix, `/home/zwitschi/StabilityMatrix/Data/README.md`) using **AlbedoBase XL v3.1-Large** at seed 55, workflow `texture_albedobase_xl` (pale marble-limestone ashlar prompt) | Civitai model 140737 — commercial image use allowed, credit required | [ ] credit line still to be added to the game's credits document before release; sidecar `T_FacadeAshlar_AI.json` records model, prompt, seed and graph |