upgrade: adopt V8.31.1 (theme 1.3/1.4 redesigns, editor deep-canvas, guided launch, component library)

Overlay 190 upstream items (V8.22→8.31) preserving trade-pro theme,
registry tests, and design docs. Re-applied full patch set on identical
anchors (discovery/env_for/blocks.css/type-mapping/locale-override/
theme_color/frontend entries/test_theme_pro_v3 mods) plus compose pins.

Verified: theme suites 35/35; dual-baseline full run 415 passed vs
pristine 386+29 ours, FAILED-set diff EMPTY (same 10 Windows env fails).
Live: container 8.31.1-dev.1 healthy, hesupipe 192 entries intact,
trade-pro build 203 pages 0 errors.

Co-Authored-By: Claude Code <noreply@anthropic.com>

scripts/check.ps1

@@ -2,7 +2,7 @@ $ErrorActionPreference = 'Stop'
 Set-Location (Join-Path $PSScriptRoot '..')
 python -m compileall -q app
 if ($LASTEXITCODE -ne 0) { exit $LASTEXITCODE }
-python scripts/regression_v821.py --report reports/v821-regression
+python scripts/regression_v824.py --timeout 65 --group-size 3
 if ($LASTEXITCODE -ne 0) { exit $LASTEXITCODE }
 Get-ChildItem app/static -Filter *.js | ForEach-Object {
   node --check $_.FullName
@@ -14,3 +14,6 @@ if (Get-Command docker -ErrorAction SilentlyContinue) {
   docker compose -f compose.enterprise.yaml config --quiet
   if ($LASTEXITCODE -ne 0) { exit $LASTEXITCODE }
 }
+
+node tests/test_nested_helpers_v823.cjs
+if ($LASTEXITCODE -ne 0) { exit $LASTEXITCODE }