Add rate limiting and improve e2e testing workflow

- Add express-rate-limit to custom endpoints for security:
  - /introspect: 100 requests per 5 minutes
  - /fakeupstreamauth/*: 20 requests per minute
  - Static files: 25 requests per 10 minutes
- Add automated e2e testing npm scripts using concurrently:
  - npm run test:e2e:integrated: Auto-starts server and runs test
  - npm run test:e2e:separate: Auto-starts both servers and runs test
- Update README with automated testing approach documentation
- Update docs/streamable-http-design.md with current file structure
- Remove redundancy in README e2e testing documentation
- Verified: All tests, linting, and e2e scripts pass with rate limiting

package-lock.json

@@ -13,6 +13,7 @@
         "cors": "^2.8.5",
         "dotenv": "^16.4.7",
         "express": "^4.21.2",
+        "express-rate-limit": "^8.0.1",
         "raw-body": "^3.0.0"
       },
       "devDependencies": {
@@ -1777,6 +1778,21 @@
         "url": "https://opencollective.com/express"
       }
     },
+    "node_modules/@modelcontextprotocol/sdk/node_modules/express-rate-limit": {
+      "version": "7.5.1",
+      "resolved": "https://artifactory.infra.ant.dev:443/artifactory/api/npm/npm-all/express-rate-limit/-/express-rate-limit-7.5.1.tgz",
+      "integrity": "sha512-7iN8iPMDzOMHPUYllBEsQdWVB6fPDMPqwjBaFrgr4Jgr/+okjvzAy+UHlYYL/Vs0OsOrMkwS6PJDkFlJwoxUnw==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 16"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/express-rate-limit"
+      },
+      "peerDependencies": {
+        "express": ">= 4.11"
+      }
+    },
     "node_modules/@modelcontextprotocol/sdk/node_modules/finalhandler": {
       "version": "2.1.0",
       "resolved": "https://registry.npmjs.org/finalhandler/-/finalhandler-2.1.0.tgz",
@@ -3850,10 +3866,13 @@
       }
     },
     "node_modules/express-rate-limit": {
-      "version": "7.5.1",
-      "resolved": "https://registry.npmjs.org/express-rate-limit/-/express-rate-limit-7.5.1.tgz",
-      "integrity": "sha512-7iN8iPMDzOMHPUYllBEsQdWVB6fPDMPqwjBaFrgr4Jgr/+okjvzAy+UHlYYL/Vs0OsOrMkwS6PJDkFlJwoxUnw==",
+      "version": "8.0.1",
+      "resolved": "https://artifactory.infra.ant.dev:443/artifactory/api/npm/npm-all/express-rate-limit/-/express-rate-limit-8.0.1.tgz",
+      "integrity": "sha512-aZVCnybn7TVmxO4BtlmnvX+nuz8qHW124KKJ8dumsBsmv5ZLxE0pYu7S2nwyRBGHHCAzdmnGyrc5U/rksSPO7Q==",
       "license": "MIT",
+      "dependencies": {
+        "ip-address": "10.0.1"
+      },
       "engines": {
         "node": ">= 16"
       },
@@ -4455,6 +4474,15 @@
       "integrity": "sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ==",
       "license": "ISC"
     },
+    "node_modules/ip-address": {
+      "version": "10.0.1",
+      "resolved": "https://artifactory.infra.ant.dev:443/artifactory/api/npm/npm-all/ip-address/-/ip-address-10.0.1.tgz",
+      "integrity": "sha512-NWv9YLW4PoW2B7xtzaS3NCot75m6nK7Icdv0o3lfMceJVRfSoQwqD4wEH5rLwoKJwUiZ/rfpiVBhnaF0FK4HoA==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 12"
+      }
+    },
     "node_modules/ipaddr.js": {
       "version": "1.9.1",
       "resolved": "https://registry.npmjs.org/ipaddr.js/-/ipaddr.js-1.9.1.tgz",