README: SVG architecture diagram replaces mermaid; embed + text fallback; assets/readme added

scripts/validate_readme_assets.py

@@ -0,0 +1,17 @@
+import io, collections, re
+import xml.etree.ElementTree as ET
+
+t = io.open('assets/readme/architecture.svg', encoding='utf-8').read()
+ET.fromstring(t)
+for bad in ('<script', 'foreignObject', '@import', 'http://fonts', 'https://fonts'):
+    assert bad not in t, 'sanitizer risk: ' + bad
+print('SVG well-formed:', len(t), 'bytes; no script/foreignObject/remote fonts')
+
+sizes = collections.Counter(re.findall(r'font-size="(\d+)"', t))
+print('font sizes:', dict(sorted(sizes.items(), key=lambda kv: -int(kv[0]))))
+
+r = io.open('README.md', encoding='utf-8').read()
+assert 'mermaid' not in r, 'mermaid still present'
+assert './assets/readme/architecture.svg' in r, 'embed missing'
+assert 'Текстовая версия схемы' in r, 'fallback missing'
+print('README ok: embed + text fallback, mermaid removed')