[Bug]: 'Add account' button does nothing when default runtime is a remote server

### Operating system
Linux (local: Debian notebook; remote host: Ubuntu VPS, Orca Remote Server via Tailscale)

### Orca version
1.4.199 on both ends (local app and `orca serve --port 6768` on the server)

### Details
**Short summary:**
With the default runtime set to a saved remote server, the "Agregar cuenta / Add account" button on the Claude and Codex account screens is not clickable — clicking it does nothing. No login flow starts.

**What happened?**
1. Set the default runtime to a saved remote Linux server ("Fortis Soluções").
2. Open the accounts screen. It correctly shows the remote scope: "Mostrando las cuentas administradas por Fortis Soluções".
3. The Claude section shows "Predeterminado del sistema / Activo" (works); the Codex section shows "Necesita iniciar sesión" (expected, no login yet).
4. Click "Agregar cuenta" (both sections). Nothing happens — no dialog, no browser flow, no error message.

**Evidence it is UI-side, not backend:**
- On the server, `orca account add --agent codex --json` works: it prints the device-code flow (`https://auth.openai.com/codex/device` + one-time code) and `claude`/`codex` CLIs are installed (Claude Code 2.1.268, codex-cli 0.153.4).
- On the server, `orca account add --json` (Claude) works: it prints the OAuth authorize URL and waits for the pasted code.
- The server daemon log shows **zero** account-related entries around the clicks, so the click never reaches the runtime.

**Expected:**
Clicking the button should start the same login flow the CLI runs (device code for Codex, OAuth URL for Claude), or at least show an error.

**Anything else:**
- Remote server runs `orca serve --port 6768 --pairing-address ` as a systemd unit, 1.4.199, runtime healthy/connected.
- Workaround in use: run `orca account add [--agent codex]` in a server terminal and complete auth in the local browser.