Don't use `--` when the `npmClient` is `pnpm`

**Description:**

When running `ionic capacitor run android --livereload --external`, I get an endless loop of `[INFO] Waiting for connectivity with pnpm...`

```log
> pnpm run ionic:serve -- --host=0.0.0.0 --port=8100
[pnpm] > theia-mobile@0.1.1 ionic:serve /home/nato/Code/github.com/Omerlo-Technologies/theia-mobile
[pnpm] > vite dev "--" "--host=0.0.0.0" "--port=8100"
[pnpm] VITE v4.3.9 ready in 474 ms
[pnpm] ➜ Local: http://localhost:5173/
[pnpm] ➜ Network: use --host to expose
[pnpm] ➜ press h to show help
[INFO] Waiting for connectivity with pnpm...
[INFO] Waiting for connectivity with pnpm...
[INFO] Waiting for connectivity with pnpm...
```

The issue is that `pnpm run ionic:serve -- --host=0.0.0.0 --port=8100` doesn't work as expected because of that `--` in the middle. `--` is useful when you want `npm` to pass additional command-line arguments to scripts, but `pnpm` isn't limited by this restriction and it passes the whole thing. When `vite` receives that, it ignores everything after it.

This can be tested:

```sh
❯ vite dev --host=0.0.0.0 --port=8100

VITE v4.3.9 ready in 527 ms

➜ Local: http://localhost:8100/
➜ Network: http://192.168.1.213:8100/
➜ Network: http://192.168.1.214:8100/
➜ press h to show help

❯ vite dev -- --host=0.0.0.0 --port=8100

VITE v4.3.9 ready in 519 ms

➜ Local: http://localhost:5173/
➜ Network: use --host to expose
➜ press h to show help
```

**Steps to Reproduce:**

1. Have a Vite app (ex: SvelteKit)
2. Setup Capacitor and Ionic
```json
{
"name": "Hello World",
"integrations": {
"capacitor": {}
},
"type": "custom",
"npmClient": "pnpm"
}
```
3. Set these scripts in `package.json`
```json
"dev:android": "ionic capacitor run android --livereload --external",
"ionic:serve": "vite dev",
```
4. Run `pnpm dev:android`

**Output:**

**My `ionic info`:**

```yaml
Ionic:

Ionic CLI : 7.1.1 (/home/nato/.local/share/pnpm/global/5/.pnpm/@ionic+cli@7.1.1/node_modules/@ionic/cli)

Capacitor:

Capacitor CLI : 5.0.5
@capacitor/android : 5.0.5
@capacitor/core : 5.0.5
@capacitor/ios : 5.0.5

Utility:

cordova-res : not installed globally
native-run : not installed globally

System:

NodeJS : v20.2.0 (/usr/bin/node)
npm : 9.7.1
OS : Linux 6.2
```

**Other Information:**

Admittedly, this *could* be seen as a `vite` issue, but I it's possible that they would consider rejecting everything after `--` as a security benefit.