It's fair to assume if you're closing Coder Desktop, you want Coder Connect to stop, so this is the default behaviour.Tailscale also stops their VPN when quitting the app, even though it works fine with the app closed.

This PR addresses#121. The underlying bug is still present in macOS, this is just a workaround, so I'm leaving the issue open.macOS calls `actionForReplacingExtension` whenever the version string(s) of the system extension living inside the Coder Desktop app bundle change.i.e. When a new version of the app is installed:1. App sends `activationRequest` (it does this on every launch, to see if the NE is installed)2. Eventually, `actionForReplacingExtension` is called, which can either return `.cancel` or `.replace`.3. Eventually,`didFinishWithResult` is called with whether the replacement was successful.(`actionForReplacingExtension` is *always* called when developing the app locally, even if the version string(s) don't differ)However, in the linked issue, we note that this replacement process is bug-prone. This bug can be worked around by deleting the system extension (in settings), and reactivating it (such as by relaunching the app).Therefore, in this PR, when `didFinishWithResult` is called following a replacement request, we instead will:1. Send a `deactivationRequest`, and wait for it to be successful.2. Send another `activationRequest`, and wait for that to be successful.Of note is that we *cannot* return `.cancel` from `actionForReplacingExtension` and then later send a `deactivationRequest`. `deactivationRequest` *always* searches for a system extension with version string(s) that match the system extension living inside the currently installed app bundle. Therefore, we have to let the replacement take place before attempting to delete it.Also of note is that a successful `deactivationRequest` of the system extension deletes the corresponding VPN configuration. This configuration is normally created by logging in, but if the user is already logged in, we'll update the UI to include a `Reconfigure VPN` button.<img width="263" alt="image" src="https://github.com/user-attachments/assets/d874821e-1696-4d17-bb3e-4ea83556f75c" />I've tested this PR in a fresh macOS 15.4 VM, upgrading from the latest release. I also forced the bug in the linked issue to occur by toggling on the VPN in System Settings before opening the new version of the app for the first time, and going through all the additional prompts did indeed prevent the issue from happening.

…eleted (#162)This fixes a bug when `Launch Coder Connect at startup` is enabled when updating the app with#161, where the app attempts to start too early, as it thinks the VPN is configured, but it was unconfigured with the deletion of the system extension.