feat(deploy): add redis compose uninstall; require Redis in install wizard

Step 2 blocks until Redis connects; uninstall-redis-compose.sh removes legacy
nexus-prod-redis container without touching host/1Panel Redis.

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

server/api/install.py

@@ -99,7 +99,7 @@ def _build_redis_url(req: InitDbRequest) -> str:
 
 
 def _resolve_redis_probe() -> tuple[str, int, str | None]:
-    """Redis target for install wizard health check (Docker uses redis:6379, not host loopback)."""
+    """Redis target for install wizard (Docker: host.docker.internal → 宿主机自建 Redis)."""
     url = os.environ.get("NEXUS_REDIS_URL", "").strip()
     if url:
         parsed = urlparse(url)
@@ -442,9 +442,9 @@ async def env_check():
             "pass": False,
         })
 
-    # Redis — 用户自行安装（1Panel/宿主机），不阻塞安装向导
+    # Redis — 须先安装并连通（宿主机/1Panel）；Docker 默认 host.docker.internal:6379
     redis_ok = False
-    redis_msg = "未检测"
+    redis_msg = "未连接"
     rh, rp, rpass = _resolve_redis_probe()
     redis_label = f"{rh}:{rp}"
     try:
@@ -454,20 +454,23 @@ async def env_check():
                 host=rh,
                 port=rp,
                 password=rpass or None,
-                socket_timeout=0.5,
+                socket_timeout=2.0,
             )
             r.ping()
             redis_ok = True
             redis_msg = f"✓ 已连接 {redis_label}"
         except Exception as e:
-            redis_msg = f"未连接 {redis_label}（可继续，步骤3配置或稍后安装 Redis）— {e}"
+            redis_msg = (
+                f"连接失败: {e}（请先在宿主机/1Panel 安装 Redis；"
+                f"Docker 部署须监听宿主机 6379 且 NEXUS_REDIS_URL 指向 {redis_label}）"
+            )
     except ImportError:
-        redis_msg = "redis 库未安装（可继续）"
+        redis_msg = "redis 库未安装"
     checks.append({
         "name": "Redis",
-        "required": "自行安装（步骤3配置）",
+        "required": "已连接",
         "current": redis_msg,
-        "pass": True,
+        "pass": redis_ok,
     })
 
     # MySQL database — user configures in step 3