v0.3.0: rendering pass, generated props, selection model and Web build

Rendering and presentation
- Shared surface-material module (src/game/materials.gd) with per-surface
  roughness/metallic/uv profiles; ACES tonemapping, glow, fog and phase-driven sky
  energy. WorldBuilder rebuilt on those profiles with facade windows that light up,
  door trim/handles, curb, lane dashes, bollards, bench, bin and planter foliage.
- NPC silhouettes: per-role clothing palettes, caps/hoods/backpacks/sunglasses,
  hands and shoes, arm/leg walk swing.
- Six generated low-poly GLB props (bollards, bench, bin, planter, newspaper box,
  hydrant) built by tools/model_pipeline.py, loaded by WorldBuilder with a
  procedural fallback; ADR-0012.

Selection and movement
- Focus ranking by view angle then distance (NpcFocus.rank_indices); Tab and the
  mouse wheel cycle nearby people initially, right click clears focus with a
  re-acquire grace, HUD shows the candidate count, Shift walks at half speed.
  ADR-0011. Windowed smoke extended to cover wheel cycling and clearing.

QA tooling
- screen_designs.py catalogue grown to 19 screens (8 scene, 11 UI) plus a `list`
  subcommand; draft generation keeps existing AI references unless --force.

Web export
- New Web preset using the non-threaded Godot template (static hosting, no
  COOP/COEP). tools/build_releases.sh exports build/web and packages
  build/step-line-web-<ver>.zip; publish_release.sh uploads it with the desktop
  artifacts. test_web_export.gd covers the preset and release wiring.

Verification
- Headless suite 177 -> 181, Python tooling 53 tests, all eight smokes pass
  (including the windowed focus/wheel smoke). Web bundle serves index.html,
  index.wasm (35 MB) and index.pck (30 MB) with HTTP 200 from a static server.
- Version 0.3.0; README, PLAN, RELEASING, TODO/DONE and MEMORY updated.

tools/build_releases.sh

@@ -10,6 +10,7 @@
 #   build/step-line-linux-<version>.x86_64
 #   build/step-line-windows-<version>.exe
 #   build/step-line-macos-<version>.zip
+#   build/step-line-web-<version>.zip  (Godot web build: static hosting, no threads)
 #
 set -euo pipefail
 
@@ -28,6 +29,26 @@ echo "==> Exporting Windows Desktop"
 echo "==> Exporting macOS"
 "$GODOT" --headless --export-release "macOS" "build/step-line-macos-${VERSION}.zip"
 
+echo "==> Exporting Web (no threads, static-hosting friendly)"
+rm -rf build/web
+mkdir -p build/web
+"$GODOT" --headless --export-release "Web" "build/web/index.html"
+# Ship the web build as a single zip so it can be downloaded and served as-is.
+rm -f "build/step-line-web-${VERSION}.zip"
+if command -v zip >/dev/null 2>&1; then
+  (cd build/web && zip -q -r "../step-line-web-${VERSION}.zip" .)
+else
+  python3 - "$PWD/build/web" "$PWD/build/step-line-web-${VERSION}.zip" <<'PYZIP'
+import os, sys, zipfile
+src, out = sys.argv[1], sys.argv[2]
+with zipfile.ZipFile(out, "w", zipfile.ZIP_DEFLATED) as archive:
+    for root, _dirs, files in os.walk(src):
+        for name in files:
+            path = os.path.join(root, name)
+            archive.write(path, os.path.relpath(path, src))
+PYZIP
+fi
+
 echo ""
 echo "Artifacts:"
 ls -la build/*"${VERSION}"*