Remove Socket.IO dependencies and Socket infrastructure

- Remove socket.io-client npm package
- Remove Socket.IO from gulpfile.js
- Remove API_PUBLIC_WS_URL config variable from all environments
- Remove Socket CSP directives (cdn.socket.io, wss:// URLs)
- Remove unused data-host attribute from job template
- Update test_headers.py to remove Socket.IO assertions
- Update deployment configs (manifest.yml, deploy-config/*.yml, .github/workflows/*.yml)

deploy-config/demo.yml

@@ -8,4 +8,3 @@ redis_enabled: 1
 nr_agent_id: '1134302465'
 nr_app_id: '1083160688'
 API_PUBLIC_URL: https://notify-api-demo.app.cloud.gov
-API_PUBLIC_WS_URL: wss://notify-api-demo.app.cloud.gov

deploy-config/production.yml

@@ -8,4 +8,3 @@ redis_enabled: 1
 nr_agent_id: '1050708682'
 nr_app_id: '1050708682'
 API_PUBLIC_URL: https://notify-api-production.app.cloud.gov
-API_PUBLIC_WS_URL: wss://notify-api-production.app.cloud.gov

deploy-config/staging.yml

@@ -8,4 +8,3 @@ redis_enabled: 1
 nr_agent_id: '1134291385'
 nr_app_id: '1031640326'
 API_PUBLIC_URL: https://notify-api-staging.app.cloud.gov
-API_PUBLIC_WS_URL: wss://notify-api-staging.app.cloud.gov