nginx: reverse-proxy legacy /scan.html /demo.html /report/* alongside /api/*

These paths are still served by the old FastAPI container (now obdx-api),
so the new landing nginx must forward them upstream instead of letting the
SPA fallback swallow them.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.gitignore

@@ -6,4 +6,5 @@ dist
 .DS_Store
 .dev-screenshot-*.png
 .playwright-mcp
+.memory
 *.log