Add 2nd optional argument for ssh config entry for Tailscale Install script for JetKVM.

[zerkz]

Add SSH Config arg (2nd after JETKVM_IP) to install-tailscale.sh, allowing you to use a public key that doesn't have to be the default convention.

I have many keys on my machine, did not want to have to reuse id_rsa or any of the other defaults expected by this script.

Assisted by Claude, reviewed/tested by me (a hooman).

❯ ./install-tailscale.sh 192.168.1.180 -s jetkvm
───────────────────────────────────────────────────────────
           JetKVM Tailscale Installation
───────────────────────────────────────────────────────────

  JetKVM IP:            192.168.1.180
  Tailscale Version:    1.88.1
  SSH Config:           jetkvm

  Note: The device will be rebooted during installation

Continue? [y/N]: y

[1/7] Checking if JetKVM device is reachable...
       Device is reachable
       Checking SSH access (Developer Mode)...
       SSH access confirmed
[2/7] Downloading Tailscale 1.88.1 checksum...
[3/7] Downloading Tailscale 1.88.1 package...
[4/7] Verifying package integrity...
       Package verification successful
[5/7] Transferring Tailscale package to JetKVM...
[6/7] Installing and configuring Tailscale on JetKVM...
       Extracting package...
       Configuring Tailscale for JetKVM...
       Rebooting JetKVM device...
       Waiting for JetKVM to reboot and come back online...
       Checking device status... (1/120s)
       Checking device status... (2/120s)
       Checking device status... (3/120s)
       Checking device status... (4/120s)
       Checking device status... (5/120s)
       Checking device status... (6/120s)
       Checking device status... (7/120s)
       JetKVM is back online with Tailscale installed!
[7/7] Starting Tailscale service...

To authenticate, visit:

        https://login.tailscale.com/a/xxxxxxxxx

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[adamshiervani]

Can you make the ssh config a flag?

[zerkz]

@adamshiervani ok, should be switched over to flag style now 👍