📝 Add missing files: README.md, config.yaml, start.sh

✨ 추가된 파일들:
- README.md: 프로젝트 문서 및 사용법 가이드
- config/config.yaml: Headscale 완전 설정 파일
- start.sh: 원클릭 자동 설치 스크립트

🔧 설정 세부사항:
- SQLite 데이터베이스 기본 설정
- Magic DNS 활성화
- Korean 시간대 설정
- 보안 설정 포함

🤖 Generated with [Claude Code](https://claude.ai/code)

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

config/config.yaml

@@ -0,0 +1,69 @@
+---
+server_url: http://localhost:8080
+listen_addr: 0.0.0.0:8080
+metrics_listen_addr: 0.0.0.0:9090
+
+private_key_path: /var/lib/headscale/private.key
+noise:
+  private_key_path: /var/lib/headscale/noise_private.key
+
+ip_prefixes:
+  - 100.64.0.0/10
+
+derp:
+  server:
+    enabled: false
+  urls:
+    - https://controlplane.tailscale.com/derpmap/default
+
+disable_check_updates: false
+ephemeral_node_inactivity_timeout: 30m
+database:
+  type: sqlite3
+  sqlite:
+    path: /var/lib/headscale/db.sqlite
+
+acme_url: https://acme-v02.api.letsencrypt.org/directory
+acme_email: ""
+
+tls_letsencrypt_hostname: ""
+tls_letsencrypt_cache_dir: /var/lib/headscale/cache
+tls_letsencrypt_challenge_type: HTTP-01
+tls_letsencrypt_listen: ":http"
+
+tls_cert_path: ""
+tls_key_path: ""
+
+log:
+  format: text
+  level: info
+
+acl_policy_path: ""
+
+dns_config:
+  override_local_dns: true
+  nameservers:
+    - 1.1.1.1
+    - 8.8.8.8
+  domains: []
+  magic_dns: true
+  base_domain: headscale.local
+
+unix_socket: /var/run/headscale/headscale.sock
+unix_socket_permission: "0770"
+
+logtail:
+  enabled: false
+
+randomize_client_port: false
+
+oidc:
+  only_start_if_oidc_is_available: true
+  issuer: ""
+  client_id: ""
+  client_secret: ""
+  scope: ["openid", "profile", "email"]
+  extra_params: {}
+  allowed_domains: []
+  allowed_users: []
+  strip_email_domain: true