"one-line-install" on Opto 22

### Current Behavior

A customer attempted to install device agent using the "one-line-instal" but failed ...

```
Checking Node.js installation...
Installing Node.js 20.19.1...
[ERROR] Node.js setup failed: failed to save Node.js download: write /tmp/nodejs-download3198778220: no space left on device
[ERROR] Installation failed: node.js setup failed: failed to save Node.js download: write /tmp/nodejs-download3198778220: no space left on device
```

To work around this, I asked the user to set env var TMPDIR to a partition with lots of space

Next, the installation failed due to Node20 version not being supported on the hardware

After running with --nodejs-version=18, it installed but is complaining about libcstd++.so.6 - but appears to actually work.

@robmarcer or I will add full logs once we get a copy.

### Expected Behavior

Consider checking size of /tmp before installation?

### Steps To Reproduce

You will need access to a groov epic (ZJ has one)

### Environment

- FlowFuse version:
- Node.js version:
- npm version:
- Platform/OS:
- Browser:

### Linked Customers

- [Customer](https://app-eu1.hubspot.com/contacts/26586079/record/0-1/3501)