Add per-service customization, stealth hardening, and BYOS support

- HTTP: configurable server_header, response_code, fake_app presets
  (apache/nginx/wordpress/phpmyadmin/iis), extra_headers, custom_body,
  static files directory mount
- SSH/Cowrie: configurable kernel_version, hardware_platform, ssh_banner,
  and users/passwords via COWRIE_USERDB_ENTRIES; switched to build mode
  so cowrie.cfg.j2 persona fields and userdb.txt generation work
- SMTP: configurable banner and MTA hostname
- MySQL: configurable version string in protocol greeting
- Redis: configurable redis_version and os string in INFO response
- BYOS: [custom-*] INI sections define bring-your-own Docker services
- Stealth: rename all *_honeypot.py → server.py; replace HONEYPOT_NAME
  env var with NODE_NAME across all 22+ service templates and plugins;
  strip "honeypot" from all in-container file content
- Config: DeckyConfig.service_config dict; INI [decky-N.svc] subsections;
  composer passes service_cfg to compose_fragment
- 350 tests passing (100%)

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

templates/imap/server.py

@@ -0,0 +1,98 @@
+#!/usr/bin/env python3
+"""
+IMAPserver.
+Presents an IMAP4rev1 banner, captures LOGIN credentials (plaintext and
+AUTHENTICATE), then returns a NO response. Logs all commands as JSON.
+"""
+
+import asyncio
+import json
+import os
+import socket
+from datetime import datetime, timezone
+
+NODE_NAME = os.environ.get("NODE_NAME", "mailserver")
+LOG_TARGET = os.environ.get("LOG_TARGET", "")
+BANNER = f"* OK [{NODE_NAME}] IMAP4rev1 Service Ready\r\n"
+
+
+def _forward(event: dict) -> None:
+    if not LOG_TARGET:
+        return
+    try:
+        host, port = LOG_TARGET.rsplit(":", 1)
+        with socket.create_connection((host, int(port)), timeout=3) as s:
+            s.sendall((json.dumps(event) + "\n").encode())
+    except Exception:
+        pass
+
+
+def _log(event_type: str, **kwargs) -> None:
+    event = {
+        "ts": datetime.now(timezone.utc).isoformat(),
+        "service": "imap",
+        "host": NODE_NAME,
+        "event": event_type,
+        **kwargs,
+    }
+    print(json.dumps(event), flush=True)
+    _forward(event)
+
+
+class IMAPProtocol(asyncio.Protocol):
+    def __init__(self):
+        self._transport = None
+        self._peer = None
+        self._buf = b""
+
+    def connection_made(self, transport):
+        self._transport = transport
+        self._peer = transport.get_extra_info("peername", ("?", 0))
+        _log("connect", src=self._peer[0], src_port=self._peer[1])
+        transport.write(BANNER.encode())
+
+    def data_received(self, data):
+        self._buf += data
+        while b"\n" in self._buf:
+            line, self._buf = self._buf.split(b"\n", 1)
+            self._handle_line(line.decode(errors="replace").strip())
+
+    def _handle_line(self, line: str):
+        parts = line.split(None, 2)
+        if not parts:
+            return
+        tag = parts[0]
+        cmd = parts[1].upper() if len(parts) > 1 else ""
+        args = parts[2] if len(parts) > 2 else ""
+
+        if cmd == "LOGIN":
+            creds = args.split(None, 1)
+            username = creds[0].strip('"') if creds else ""
+            password = creds[1].strip('"') if len(creds) > 1 else ""
+            _log("auth", src=self._peer[0], username=username, password=password)
+            self._transport.write(f"{tag} NO [AUTHENTICATIONFAILED] Invalid credentials\r\n".encode())
+        elif cmd == "CAPABILITY":
+            self._transport.write(b"* CAPABILITY IMAP4rev1 AUTH=PLAIN AUTH=LOGIN\r\n")
+            self._transport.write(f"{tag} OK CAPABILITY completed\r\n".encode())
+        elif cmd == "LOGOUT":
+            self._transport.write(b"* BYE IMAP4rev1 Server logging out\r\n")
+            self._transport.write(f"{tag} OK LOGOUT completed\r\n".encode())
+            self._transport.close()
+        else:
+            _log("command", src=self._peer[0], cmd=line[:128])
+            self._transport.write(f"{tag} BAD Command not recognized\r\n".encode())
+
+    def connection_lost(self, exc):
+        _log("disconnect", src=self._peer[0] if self._peer else "?")
+
+
+async def main():
+    _log("startup", msg=f"IMAP server starting as {NODE_NAME}")
+    loop = asyncio.get_running_loop()
+    server = await loop.create_server(IMAPProtocol, "0.0.0.0", 143)
+    async with server:
+        await server.serve_forever()
+
+
+if __name__ == "__main__":
+    asyncio.run(main())