feat: 新增 TCP checker，支持端口可达性探测与 banner 读取

- 新增 src/server/checker/runner/tcp/ 自包含目录（types/schema/validate/execute/expect）
- 注册 TcpChecker 到 checkerRegistry，schema/engine/store/config-loader 自动委托
- 支持 expect.connected 正反向语义（默认期待可达，可配置期待不可达）
- 支持 readBanner opt-in banner 读取，受 bannerReadTimeout + maxBannerBytes 双重限制
- 复用电有 expect/operator/duration/failure 基础设施
- 新增 3 个测试文件 51 条用例（execute/validate/expect），全量 634 测试通过
- 更新 README/DEVELOPMENT/probes.example.yaml，新增 tcp-checker capability spec

probe-config.schema.json

@@ -62,6 +62,27 @@
           "additionalProperties": false,
           "type": "object",
           "properties": {}
+        },
+        "tcp": {
+          "additionalProperties": false,
+          "type": "object",
+          "properties": {
+            "bannerReadTimeout": {
+              "minimum": 0,
+              "type": "number"
+            },
+            "maxBannerBytes": {
+              "anyOf": [
+                {
+                  "type": "string"
+                },
+                {
+                  "minimum": 0,
+                  "type": "integer"
+                }
+              ]
+            }
+          }
         }
       }
     },
@@ -964,6 +985,163 @@
                 }
               }
             }
+          },
+          {
+            "additionalProperties": false,
+            "type": "object",
+            "required": [
+              "id",
+              "type",
+              "tcp"
+            ],
+            "properties": {
+              "description": {
+                "anyOf": [
+                  {
+                    "type": "null"
+                  },
+                  {
+                    "maxLength": 500,
+                    "type": "string"
+                  }
+                ]
+              },
+              "expect": {
+                "additionalProperties": false,
+                "type": "object",
+                "properties": {
+                  "banner": {
+                    "additionalProperties": false,
+                    "minProperties": 1,
+                    "type": "object",
+                    "properties": {
+                      "contains": {
+                        "type": "string"
+                      },
+                      "empty": {
+                        "type": "boolean"
+                      },
+                      "equals": {
+                        "anyOf": [
+                          {
+                            "type": "string"
+                          },
+                          {
+                            "type": "number"
+                          },
+                          {
+                            "type": "boolean"
+                          },
+                          {
+                            "type": "null"
+                          },
+                          {
+                            "items": {},
+                            "type": "array"
+                          },
+                          {
+                            "additionalProperties": {},
+                            "type": "object"
+                          }
+                        ]
+                      },
+                      "exists": {
+                        "type": "boolean"
+                      },
+                      "gt": {
+                        "type": "number"
+                      },
+                      "gte": {
+                        "type": "number"
+                      },
+                      "lt": {
+                        "type": "number"
+                      },
+                      "lte": {
+                        "type": "number"
+                      },
+                      "match": {
+                        "type": "string"
+                      }
+                    }
+                  },
+                  "connected": {
+                    "type": "boolean"
+                  },
+                  "maxDurationMs": {
+                    "minimum": 0,
+                    "type": "number"
+                  }
+                }
+              },
+              "group": {
+                "type": "string"
+              },
+              "id": {
+                "maxLength": 30,
+                "minLength": 1,
+                "type": "string"
+              },
+              "interval": {
+                "type": "string"
+              },
+              "name": {
+                "anyOf": [
+                  {
+                    "type": "null"
+                  },
+                  {
+                    "maxLength": 30,
+                    "minLength": 1,
+                    "type": "string"
+                  }
+                ]
+              },
+              "timeout": {
+                "type": "string"
+              },
+              "type": {
+                "const": "tcp",
+                "type": "string"
+              },
+              "tcp": {
+                "additionalProperties": false,
+                "type": "object",
+                "required": [
+                  "host",
+                  "port"
+                ],
+                "properties": {
+                  "bannerReadTimeout": {
+                    "minimum": 0,
+                    "type": "number"
+                  },
+                  "host": {
+                    "minLength": 1,
+                    "type": "string"
+                  },
+                  "maxBannerBytes": {
+                    "anyOf": [
+                      {
+                        "type": "string"
+                      },
+                      {
+                        "minimum": 0,
+                        "type": "integer"
+                      }
+                    ]
+                  },
+                  "port": {
+                    "maximum": 65535,
+                    "minimum": 1,
+                    "type": "integer"
+                  },
+                  "readBanner": {
+                    "type": "boolean"
+                  }
+                }
+              }
+            }
           }
         ]
       }