feat: Implement virtual hosting for multi-domain Gemini server

- Add hostname-based request routing for multiple capsules per server
- Parse virtual host configs from TOML sections ([hostname])
- Implement per-host certificate and content isolation
- Add comprehensive virtual host testing and validation
- Update docs and examples for multi-host deployments

This enables Pollux to serve multiple Gemini domains from one instance,
providing the foundation for multi-tenant Gemini hosting.

tests/gemini_test_client.py

@@ -8,6 +8,7 @@ Used by integration tests for rate limiting validation.
 Usage: python3 tests/gemini_test_client.py gemini://host:port/path
 """
 
+import os
 import sys
 import socket
 import ssl
@@ -19,51 +20,65 @@ def main():
     
     url = sys.argv[1]
     
-    # Parse URL (basic parsing)
-    if not url.startswith('gemini://'):
-        print("Error: URL must start with gemini://", file=sys.stderr)
-        sys.exit(1)
-    
-    url_parts = url[9:].split('/', 1)  # Remove gemini://
-    host_port = url_parts[0]
-    path = '/' + url_parts[1] if len(url_parts) > 1 else '/'
-    
-    if ':' in host_port:
-        host, port = host_port.rsplit(':', 1)
-        port = int(port)
+    # Parse URL (basic parsing) - allow any protocol for testing
+    if url.startswith('gemini://'):
+        url_parts = url[9:].split('/', 1)  # Remove gemini://
+        host = url_parts[0]
+        path = '/' + url_parts[1] if len(url_parts) > 1 else '/'
     else:
-        host = host_port
-        port = 1965
-    
+        # For non-gemini URLs, try to extract host anyway for testing
+        if '://' in url:
+            protocol, rest = url.split('://', 1)
+            url_parts = rest.split('/', 1)
+            host = url_parts[0]
+            path = '/' + url_parts[1] if len(url_parts) > 1 else '/'
+        else:
+            # No protocol, assume it's host/path
+            url_parts = url.split('/', 1)
+            host = url_parts[0]
+            path = '/' + url_parts[1] if len(url_parts) > 1 else '/'
+
+    # Get port from environment or use default
+    port = int(os.environ.get('GEMINI_PORT', '1965'))
+
+    # Allow overriding the connection host (useful for testing with localhost)
+    connect_host = os.environ.get('GEMINI_CONNECT_HOST', host)
+
     try:
-        # Create SSL connection
-        context = ssl.create_default_context()
+        # Create SSL connection with permissive settings for self-signed certs
+        context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
         context.check_hostname = False
         context.verify_mode = ssl.CERT_NONE
-        
-        sock = socket.create_connection((host, port), timeout=5.0)
+        # Load default certificates to avoid some SSL issues
+        context.load_default_certs()
+
+        sock = socket.create_connection((connect_host, port), timeout=5.0)
         ssl_sock = context.wrap_socket(sock, server_hostname=host)
-        
-        # Send request
+
+        # Send request (full URL for Gemini protocol over TLS)
         request = f"{url}\r\n"
         ssl_sock.send(request.encode('utf-8'))
-        
-        # Read response header
+
+        # Read full response (header + body)
         response = b''
-        while b'\r\n' not in response and len(response) < 1024:
-            data = ssl_sock.recv(1)
-            if not data:
+        while len(response) < 1024:  # Read up to 1KB for test responses
+            try:
+                data = ssl_sock.recv(1024)
+                if not data:
+                    break
+                response += data
+            except:
                 break
-            response += data
-        
+
         ssl_sock.close()
-        
+
         if response:
-            status_line = response.decode('utf-8', errors='ignore').split('\r\n')[0]
-            print(status_line)
+            # Decode and return the full response
+            full_response = response.decode('utf-8', errors='ignore')
+            print(full_response.strip())
         else:
             print("Error: No response")
-            
+
     except Exception as e:
         print(f"Error: {e}")