* In server/index.ts

- in createCustomFetch function
    - convert finalHeaders to headers object for node-fetch compatibility
    - for SSE streams, convert node stream to response body to web ReadableStream since EventSource polyfill expects web-compatible stream

* In package-lock.json and package.json
  - add node-fetch as a dependency

This fixes #600

package-lock.json

@@ -19,6 +19,7 @@
         "@modelcontextprotocol/inspector-server": "^0.16.7",
         "@modelcontextprotocol/sdk": "^1.18.0",
         "concurrently": "^9.2.0",
+        "node-fetch": "^3.3.2",
         "open": "^10.2.0",
         "shell-quote": "^1.8.3",
         "spawn-rx": "^5.1.2",
@@ -5103,6 +5104,15 @@
       "devOptional": true,
       "license": "MIT"
     },
+    "node_modules/data-uri-to-buffer": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/data-uri-to-buffer/-/data-uri-to-buffer-4.0.1.tgz",
+      "integrity": "sha512-0R9ikRb668HB7QDxT1vkpuUBtqc53YyAwMwGeUFKRojY/NWKvdZ+9UYtRfGmhqNbRkTSVpMbmyhXipFFv2cb/A==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 12"
+      }
+    },
     "node_modules/data-urls": {
       "version": "3.0.2",
       "resolved": "https://registry.npmjs.org/data-urls/-/data-urls-3.0.2.tgz",
@@ -5970,6 +5980,29 @@
         "bser": "2.1.1"
       }
     },
+    "node_modules/fetch-blob": {
+      "version": "3.2.0",
+      "resolved": "https://registry.npmjs.org/fetch-blob/-/fetch-blob-3.2.0.tgz",
+      "integrity": "sha512-7yAQpD2UMJzLi1Dqv7qFYnPbaPx7ZfFK6PiIxQ4PfkGPyNyl2Ugx+a/umUonmKqjhM4DnfbMvdX6otXq83soQQ==",
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/jimmywarting"
+        },
+        {
+          "type": "paypal",
+          "url": "https://paypal.me/jimmywarting"
+        }
+      ],
+      "license": "MIT",
+      "dependencies": {
+        "node-domexception": "^1.0.0",
+        "web-streams-polyfill": "^3.0.3"
+      },
+      "engines": {
+        "node": "^12.20 || >= 14.13"
+      }
+    },
     "node_modules/file-entry-cache": {
       "version": "8.0.0",
       "resolved": "https://registry.npmjs.org/file-entry-cache/-/file-entry-cache-8.0.0.tgz",
@@ -6154,6 +6187,18 @@
         "node": ">= 0.6"
       }
     },
+    "node_modules/formdata-polyfill": {
+      "version": "4.0.10",
+      "resolved": "https://registry.npmjs.org/formdata-polyfill/-/formdata-polyfill-4.0.10.tgz",
+      "integrity": "sha512-buewHzMvYL29jdeQTVILecSaZKnt/RJWjoZCF5OW60Z67/GmSLBkOFM7qh1PI3zFNtJbaZL5eQu1vLfazOwj4g==",
+      "license": "MIT",
+      "dependencies": {
+        "fetch-blob": "^3.1.2"
+      },
+      "engines": {
+        "node": ">=12.20.0"
+      }
+    },
     "node_modules/forwarded": {
       "version": "0.2.0",
       "resolved": "https://registry.npmjs.org/forwarded/-/forwarded-0.2.0.tgz",
@@ -8716,6 +8761,44 @@
         "node": ">= 0.6"
       }
     },
+    "node_modules/node-domexception": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/node-domexception/-/node-domexception-1.0.0.tgz",
+      "integrity": "sha512-/jKZoMpw0F8GRwl4/eLROPA3cfcXtLApP0QzLmUT/HuPCZWyB7IY9ZrMeKw2O/nFIqPQB3PVM9aYm0F312AXDQ==",
+      "deprecated": "Use your platform's native DOMException instead",
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/jimmywarting"
+        },
+        {
+          "type": "github",
+          "url": "https://paypal.me/jimmywarting"
+        }
+      ],
+      "license": "MIT",
+      "engines": {
+        "node": ">=10.5.0"
+      }
+    },
+    "node_modules/node-fetch": {
+      "version": "3.3.2",
+      "resolved": "https://registry.npmjs.org/node-fetch/-/node-fetch-3.3.2.tgz",
+      "integrity": "sha512-dRB78srN/l6gqWulah9SrxeYnxeddIG30+GOqK/9OlLVyLg3HPnr6SqOWTWOXKRwC2eGYCkZ59NNuSgvSrpgOA==",
+      "license": "MIT",
+      "dependencies": {
+        "data-uri-to-buffer": "^4.0.0",
+        "fetch-blob": "^3.1.4",
+        "formdata-polyfill": "^4.0.10"
+      },
+      "engines": {
+        "node": "^12.20.0 || ^14.13.1 || >=16.0.0"
+      },
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/node-fetch"
+      }
+    },
     "node_modules/node-int64": {
       "version": "0.4.0",
       "resolved": "https://registry.npmjs.org/node-int64/-/node-int64-0.4.0.tgz",
@@ -11504,6 +11587,15 @@
         "makeerror": "1.0.12"
       }
     },
+    "node_modules/web-streams-polyfill": {
+      "version": "3.3.3",
+      "resolved": "https://registry.npmjs.org/web-streams-polyfill/-/web-streams-polyfill-3.3.3.tgz",
+      "integrity": "sha512-d2JWLCivmZYTSIoge9MsgFCZrt571BikcWGYkjC1khllbTeDlGqZ2D8vD8E/lJa8WGWbb7Plm8/XJYV7IJHZZw==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 8"
+      }
+    },
     "node_modules/webidl-conversions": {
       "version": "7.0.0",
       "resolved": "https://registry.npmjs.org/webidl-conversions/-/webidl-conversions-7.0.0.tgz",