Add the optional Forward+ desktop HQ build

Package a Forward+ preset with volumetric fog, SDFGI and a volumetric flashlight
for a separate Linux/Windows Desktop HQ zip. Gate the effects on a real
RenderingDevice, tune LATE fog, and adapt local light falloff for Godot 4.7.
Record the Compatibility/Forward+ A/B captures and metrics, add the artifact to
the build/publish scripts, and keep the default Compatibility/Web path
unchanged. Headless 231/231, Python 87/87; exported HQ binary boots with Vulkan.

TODO.md

@@ -3,31 +3,11 @@
 Work is grouped by theme. Each item should be small enough to complete and verify on its own;
 see `AGENTS.md` for the workflow and `MEMORY.md` for the decisions behind these plans.
 
-## Forward+ desktop preset and a volumetric flashlight (v0.7.1)
-
-The Compatibility renderer has no volumetrics, so the flashlight is a tight pool of light with
-no visible shaft. A second desktop build can render it properly without touching the CI/default
-path.
-
-- [ ] Write the preset as an `override.cfg` (Godot reads it beside the binary/project) that sets
-      `rendering/renderer/rendering_method="forward_plus"`, enables `volumetric_fog_*` and SDFGI,
-      and keeps the Compatibility build as the default (`project.godot` unchanged).
-- [ ] Gate the effect in code: only give the flashlight a volumetric component when the renderer
-      is Forward+ (`RenderingServer.get_rendering_device() != null`), so Web/CI builds are
-      untouched and the existing headless tests keep passing.
-- [ ] Tune `light_volumetric_fog_energy`/`fog_density` for the LATE phase and re-check the
-      entrance so the shaft does not wash the facade again (the reason the wide cone was cut).
-- [ ] A/B the two renderers with `capture_realism.gd` (same stages, two `--out` dirs) and record
-      the diff + judge scores in `docs/screens/realism/<date>-forward-plus/`.
-- [ ] Add the preset to `tools/build_releases.sh` and `docs/RELEASING.md` as an optional
-      "desktop HQ" artifact, and note the runtime requirement (Vulkan driver) in `README.md`.
-- [ ] Test: a headless run must still boot when Forward+ is unavailable (the preset must degrade
-      to Compatibility instead of failing to start).
-
 ## Realism follow-ups (deferred)
 
-- [ ] Re-run the screen-design judge for `12-joke-shop` / `13-studio-arrival` when
-      `OPENROUTER_API_KEY` is valid; the 2026-11-01 attempt failed with an invalid-key HTTP 400.
+- [ ] Re-run the screen-design judge for `12-joke-shop`, `13-studio-arrival` and the
+      Forward+ A/B when `OPENROUTER_API_KEY` is valid; the 2026-11-01 attempt failed with an
+      invalid-key HTTP 400.
 - [ ] Capture a hooded/winter NPC close-up once a scenario spawns types 5-7 (the explicit
       `--portrait-type` override is already in `capture_realism.gd`).
 - [ ] Human-authored tree/hedge silhouettes: the whole scene now reads well except the foliage,