replace NPM with vanilla nginx + certbot

- nginx:alpine replaces nginx-proxy-manager
- certbot on host with standalone issuance and auto-renewal
- per-site nginx configs in conf.d/ (HTTP->HTTPS, bare->www)
- container names use underscores (timothykim_net)
- setup.sh: automated cert issuance, dynamic app startup
- deploy.sh: nginx -t guard, graceful image-not-found
- new-app.sh: Gitea API repo creation, nginx conf generation
- add ARCHITECTURE.md, USECASES.md, CLAUDE.md
- remove old NPM data/certs from tracking

docker/nginx/conf.d/timothykim.net.conf

@@ -0,0 +1,48 @@
+# Redirect HTTP to HTTPS, bare domain to www
+server {
+    listen 80;
+    listen [::]:80;
+    server_name timothykim.net www.timothykim.net;
+
+    location /.well-known/acme-challenge/ {
+        root /var/www/certbot;
+    }
+
+    location / {
+        return 301 https://www.timothykim.net$request_uri;
+    }
+}
+
+# Redirect bare HTTPS domain to www
+server {
+    listen 443 ssl;
+    listen [::]:443 ssl;
+    http2 on;
+    server_name timothykim.net;
+
+    ssl_certificate     /etc/letsencrypt/live/timothykim.net/fullchain.pem;
+    ssl_certificate_key /etc/letsencrypt/live/timothykim.net/privkey.pem;
+
+    return 301 https://www.timothykim.net$request_uri;
+}
+
+# Main site
+server {
+    listen 443 ssl;
+    listen [::]:443 ssl;
+    http2 on;
+    server_name www.timothykim.net;
+
+    ssl_certificate     /etc/letsencrypt/live/timothykim.net/fullchain.pem;
+    ssl_certificate_key /etc/letsencrypt/live/timothykim.net/privkey.pem;
+
+    add_header Strict-Transport-Security "max-age=63072000; preload" always;
+
+    location / {
+        proxy_pass http://timothykim_net:80;
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header X-Forwarded-Proto $scheme;
+    }
+}