Registration verification check in Test-Installation never detects successful registration (wrong match string + static log window) #154

The registration-verification loop in Test-Installation produces a false "did not register" warning even when the agent registers successfully. Two independent bugs, either of which alone would cause this:

$didAgentRegister = $false
for ($i = 0; $i -le 40; $i++) {
    if (Test-Path "$($HuntressDirectory)\HuntressAgent.log") {
        $linesFromLog = Get-Content "$($HuntressDirectory)\HuntressAgent.log" | Select-Object -first 4
        ForEach ($line in $linesFromLog) {
            if ($line -like "*Huntress agent registered*") {
                LogMessage "Agent successfully registered in $($i/4) seconds"
                $didAgentRegister = $true
                Start-Sleep -Milliseconds 250
                $i=100
            }
        }
    }
    Start-Sleep -Milliseconds 250
}
if ( ! $didAgentRegister) {
    $err = "WARNING: It does not appear the agent has successfully registered. Check 3rd party AV exclusion lists to ensure Huntress is excluded."
    LogMessage ($err + $SupportMessage)
}

Bug 1 — match string doesn't exist in current log output. The check looks for the literal substring Huntress agent registered. Current agent versions log structured JSON instead, with a message like:

{"level":"info","time":"2026-07-30T13:20:12-04:00","message":"registered agent#17645331 with portal in 1.0627451s"}

That string never contains Huntress agent registered, so the condition can never be true against present-day log output regardless of whether registration actually succeeded.

Bug 2 — the read window is static and never advances. Select-Object -first 4 reads the same first 4 lines of the file on every iteration of the loop (all 40 passes, every 250ms). It never looks further into the file and never tracks what's already been read. In a real log, registration-related lines commonly land past line 4 — in one capture, the registration confirmation was line 8, preceded by service-configuration and Rio-path warning lines:

1  configuring HuntressAgent service
2  unable to open HKLM\SOFTWARE\Huntress Labs\Huntress: ...
3  Rio.exe version: fork/exec ... path not found
4  unable to open HKLM\SOFTWARE\Huntress Labs\Huntress: ...
5  registering HuntressAgent service
6  Rio.exe version: fork/exec ... path not found
7  registration data: {...}
8  registered agent#17645331 with portal in 1.0627451s

Since the loop only ever inspects lines 1-4, it structurally cannot see line 8 no matter how many of the 40 iterations run. This is independent of bug 1 — fixing only the match string would still fail here, and fixing only the window would still fail on the wording mismatch.

Impact: The install script logs a spurious "It does not appear the agent has successfully registered... Check 3rd party AV exclusion lists" warning on every install, even fully successful ones, which is misleading during troubleshooting and could send techs chasing AV exclusions on machines that registered fine.

Suggested fix: Update the match to the current structured log format (e.g. match on "registered agent# or parse the JSON and check the message field), and replace Select-Object -first 4 with a tail-based read (Get-Content -Tail N, or track byte/line offset across iterations) so new lines appended during the wait are actually inspected rather than re-reading the same head of the file.