fix: connector-instagram entrypoint must be compiled dist

The T-HUB package pointed main at src/index.ts — node 22 type-stripping
executed it at runtime and crashed the api on the parameter properties
(authorizationUrl/connectionId). main now targets dist/index.js like every
other connector package; tsconfig copied from connector-mastodon.

packages/connector-instagram/package.json

@@ -3,7 +3,7 @@
   "private": true,
   "version": "0.1.0",
   "type": "module",
-  "main": "src/index.ts",
+  "main": "dist/index.js",
   "scripts": {
     "build": "tsc -p tsconfig.json",
     "lint": "eslint src",
@@ -18,5 +18,6 @@
     "@types/node": "^22.20.5",
     "typescript": "^5.5.4",
     "vitest": "^2.0.5"
-  }
-}
+  },
+  "types": "dist/index.d.ts"
+}