feat(web): tane.comunes.org landing + localized app screenshots

- Hugo site (site/): EN/ES intro + legal (generated from docs/legal), an
  ES/EN About page from docs/{que-es-tane,what-is-tane}.md, seed-green theme,
  responsive header, store-badge placeholders, multi-stage Hugo->nginx image.
- Golden screenshot harness (test/screenshots/): en,es,fr,de,pt,ja + RTL demo,
  real fonts via DejaVu Sans + FontManifest; skip-by-default tag so CI stays
  green. collect_screenshots.sh feeds site/ and fastlane phoneScreenshots.
- Drop editorial notes from the public explainer.

site/build-legal.sh

@@ -0,0 +1,71 @@
+#!/usr/bin/env bash
+# Generates the Hugo legal pages from docs/legal/ — the single source of truth.
+# Each doc's first "# Heading" becomes the page title (and is stripped from the
+# body so it isn't rendered twice). Run from site/ whenever the legal docs change:
+#   ./build-legal.sh
+# The generated content/legal/<slug>.<lang>.md files are committed so the Docker
+# build only needs site/.
+set -euo pipefail
+
+site_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+legal_src="$(cd "$site_dir/../docs/legal" && pwd)"
+out="$site_dir/content/legal"
+
+# slug | English master | Spanish mirror | menu weight
+rows=(
+  "privacy|privacy-policy.md|politica-de-privacidad.md|1"
+  "terms|terms-of-use.md|condiciones-de-uso.md|2"
+  "rules|community-rules.md|normas-de-la-comunidad.md|3"
+  "seeds|seed-legality-notice.md|aviso-sobre-semillas.md|4"
+)
+
+emit() { # <src-md> <out-md> <slug> <weight>
+  local src="$1" dst="$2" slug="$3" weight="$4"
+  # First "# ..." line -> title; everything after that line -> body. Strip a
+  # leading "Tane — " so it doesn't collide with the site title suffix in <title>.
+  local title
+  title="$(sed -n 's/^# \(.*\)/\1/p' "$src" | head -n1 \
+    | sed -E 's/^Tane[[:space:]]*(—|–|-)[[:space:]]*//')"
+  {
+    printf -- '---\n'
+    printf 'title: "%s"\n' "${title//\"/\\\"}"
+    printf 'slug: "%s"\n' "$slug"
+    printf 'weight: %s\n' "$weight"
+    printf 'translationKey: "legal-%s"\n' "$slug"
+    printf -- '---\n\n'
+    # Drop the first H1 line, keep the rest verbatim.
+    awk 'NR==1 && /^# /{next} {print}' "$src"
+  } > "$dst"
+  echo "  $(basename "$dst")  <-  $(basename "$src")"
+}
+
+for row in "${rows[@]}"; do
+  IFS='|' read -r slug en es weight <<<"$row"
+  emit "$legal_src/$en"    "$out/$slug.en.md" "$slug" "$weight"
+  emit "$legal_src/es/$es" "$out/$slug.es.md" "$slug" "$weight"
+done
+
+echo "Generated legal pages in $out"
+
+# --- Plain-language "About" page, generated from the docs/ explainers ---------
+# Each page uses its own fixed title (not the doc's H1) and drops the first H1.
+docs_dir="$(cd "$site_dir/../docs" && pwd)"
+emit_about() { # <src-md> <out-md> <title> <description>
+  local src="$1" dst="$2" title="$3" desc="$4"
+  [[ -f "$src" ]] || return 0
+  {
+    printf -- '---\n'
+    printf 'title: "%s"\n' "$title"
+    printf 'slug: "about"\n'
+    printf 'translationKey: "about"\n'
+    printf 'description: "%s"\n' "$desc"
+    printf -- '---\n\n'
+    awk 'NR==1 && /^# /{next} {print}' "$src"
+  } > "$dst"
+  echo "Generated $(basename "$dst")  <-  $(basename "$src")"
+}
+
+emit_about "$docs_dir/que-es-tane.md"  "$site_dir/content/about.es.md" \
+  "Qué es Tane" "Tane explicada para todos los públicos."
+emit_about "$docs_dir/what-is-tane.md" "$site_dir/content/about.en.md" \
+  "What is Tane" "Tane explained for everyone."