feat(nanoclaude): 배포 준비 — Dockerfile + self-SSH 로컬 분기

- Dockerfile: infra/ 복사, openssh-client, healthcheck 추가
- requirements.txt: asyncssh, python-dotenv 추가
- core/ssh.py: INFRA_LOCAL_HOST 환경변수로 self-SSH 대신 로컬 실행

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

infra/core/ssh.py

@@ -5,17 +5,24 @@ Provides run_command() which handles:
 - Password auth + sudo (company NAS)
 - Timeout / retry
 - Structured error classification
+- Local execution for self-host (INFRA_LOCAL_HOST env)
 """
 
 from __future__ import annotations
 
 import asyncio
+import os
 from datetime import datetime, timezone
 
 import asyncssh
 
 from ..config import HostConfig, SSH_TIMEOUT, CMD_TIMEOUT, MAX_RETRIES
 
+# If set, commands targeting this host use run_local() instead of SSH.
+# Avoids self-SSH issues in Docker containers (Tailscale routing, overhead).
+# Example: INFRA_LOCAL_HOST=gpu
+_LOCAL_HOST = os.getenv("INFRA_LOCAL_HOST", "")
+
 
 class SSHError(Exception):
     """Typed SSH error with error_type classification."""
@@ -45,6 +52,15 @@ async def _connect(host: HostConfig) -> asyncssh.SSHClientConnection:
     return await asyncssh.connect(**kwargs)
 
 
+def _is_local_host(host: HostConfig) -> bool:
+    """Check if this host should use local execution instead of SSH."""
+    if not _LOCAL_HOST:
+        return False
+    from ..config import HOSTS
+    local_cfg = HOSTS.get(_LOCAL_HOST)
+    return local_cfg is not None and host.ip == local_cfg.ip
+
+
 async def run_command(
     host: HostConfig,
     command: str,
@@ -53,9 +69,14 @@ async def run_command(
 ) -> tuple[str, str]:
     """Run a command on remote host. Returns (stdout, stderr).
 
+    If host matches INFRA_LOCAL_HOST, runs locally instead of SSH.
     For NAS with sudo: wraps command with sudo using password via stdin.
     Raises SSHError with typed error_type on failure.
     """
+    # Local execution for self-host
+    if _is_local_host(host):
+        return await run_local(command, timeout=timeout)
+
     if use_sudo and host.needs_sudo and host.password:
         # Pipe password to sudo via stdin
         command = f"echo '{host.password}' | sudo -S {command}"