[codex] Improve proxy pool UX/UI

[OziNetworkVN]

What changed

• refactored the proxy pool page into a searchable, sortable table layout
• added row selection and bulk actions for test, activate, deactivate, and delete
• introduced a bulk proxy-pool API endpoint so multi-item operations run in one request
• improved row-level visibility for masked proxy host, strict mode, binding count, and last test status

Why

The existing proxy pool screen supported only single-item CRUD comfortably. Managing many proxies was slow and error-prone, especially when operators needed to review status or apply the same action across multiple entries.

Impact

• proxy pool management is faster for larger proxy lists
• destructive bulk delete now reports items still bound to connections instead of failing silently
• the dashboard UX is more aligned with operational workflows for proxy maintenance

Validation

• started the app locally with npm run dev and verified http://localhost:20128 responded with HTTP 200
• attempted a production build with npx next build --webpack on Windows, but the repo currently hits an environment-specific webpack error while scanning C:\Users\Admin\Application Data (EPERM)