Revert frontend authentication flow changes from #21

[Copilot]

This reverts the frontend-side authentication handling introduced in 0a72cc08aa631f8c732c0b293dbc835bd52764cc. The goal is to restore the previous dashboard behavior and remove the client-managed login state and routing guards added in that change.

• Scope

  • Reverts the frontend auth flow added in the dashboard UI.
  • Restores the previous CLI wrapper scripts used for local serve/build/lint commands.

• Authentication rollback

  • Removes client-side login state storage from sessionStorage.
  • Removes the global Axios 401 interceptor and router-level auth verification/redirect logic.
  • Restores the previous login/logout behavior without frontend-managed redirect state.

• UI rollback

  • Reverts the login page from AJAX form submission back to standard form post behavior.
  • Reverts navbar logout handling from JS-triggered logout back to link-based logout behavior.

• Tooling rollback

  • Restores scripts/vue-cli-service.js and scripts/webpack-dev-server-compat.js.
  • Switches package scripts back to the wrapper-based commands.

{
  "scripts": {
    "lint": "node scripts/vue-cli-service.js lint",
    "serve": "node scripts/vue-cli-service.js serve",
    "build": "node scripts/vue-cli-service.js build"
  }
}