Add Docsify docs server with nginx

Move docs into docs/ directory, add Docsify for markdown rendering.
Standalone Docker stack (nginx:alpine) on port 8090.
wiring.html served as native HTML with correct MIME type.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

nginx.conf

@@ -0,0 +1,20 @@
+server {
+    listen 80;
+    root /usr/share/nginx/html;
+    index index.html;
+
+    types {
+        text/html html;
+        text/markdown md;
+        text/css css;
+        application/javascript js;
+        application/json json;
+        image/png png;
+        image/jpeg jpg jpeg;
+        image/svg+xml svg;
+    }
+
+    location / {
+        try_files $uri $uri/ /index.html;
+    }
+}