feat: add web admin panel for node management

Add Flask panel with login, add/delete nodes, and share link copy.
Generate sing-box config from SQLite; add uninstall script and clean install flow.
Panel served at https://DOMAIN:8444 via nginx.

Co-authored-by: Cursor <cursoragent@cursor.com>

panel/links.py

@@ -0,0 +1,37 @@
+"""分享链接生成。"""
+from __future__ import annotations
+
+import os
+from pathlib import Path
+from urllib.parse import quote
+
+
+def load_env() -> dict[str, str]:
+    root = Path(os.environ.get("JIEDIAN_ROOT", Path(__file__).resolve().parents[1]))
+    env: dict[str, str] = {}
+    for line in (root / ".env").read_text(encoding="utf-8").splitlines():
+        line = line.strip()
+        if not line or line.startswith("#") or "=" not in line:
+            continue
+        key, _, value = line.partition("=")
+        env[key.strip()] = value.strip()
+    return env
+
+
+def build_links(node: dict, env: dict | None = None) -> dict[str, str]:
+    env = env or load_env()
+    vps_ip = env["VPS_IP"]
+    domain = env["DOMAIN"]
+    reality_sni = env.get("REALITY_SERVER_NAME", "www.microsoft.com")
+    public_key = env["REALITY_PUBLIC_KEY"]
+    short_id = env["REALITY_SHORT_ID"]
+    name = quote(node["name"])
+
+    vless = (
+        f"vless://{node['uuid']}@{vps_ip}:443"
+        f"?encryption=none&flow=xtls-rprx-vision&security=reality"
+        f"&sni={reality_sni}&fp=chrome&pbk={public_key}&sid={short_id}"
+        f"&type=tcp#{name}"
+    )
+    hy2 = f"hy2://{node['hy2_password']}@{domain}:8443?sni={domain}#{name}-Hy2"
+    return {"vless": vless, "hy2": hy2}