test: strengthen Cypress e2e tests with real API assertions

- Remove blanket uncaught:exception suppressor (API-only tests)
- Trim smoke test to single infra-verification assertion
- Rewrite health test with strict status/field assertions, no failOnStatusCode
- Add session CRUD tests (create, get, list, delete, 404 cases, cleanup)
- Use Cypress.env('API_URL') instead of baseUrl to avoid blocking smoke tests
- Remove unused main and type fields from package.json

package.json

@@ -2,7 +2,6 @@
   "name": "lovdata-chat",
   "version": "1.0.0",
   "description": "A web-based chat interface that allows users to interact with Large Language Models (LLMs) equipped with Norwegian legal research tools from the Lovdata MCP server.",
-  "main": "index.js",
   "directories": {
     "doc": "docs"
   },
@@ -18,7 +17,6 @@
   "keywords": [],
   "author": "",
   "license": "ISC",
-  "type": "commonjs",
   "devDependencies": {
     "cypress": "^15.10.0"
   }