Fix PowerShell $Host reserved variable conflict in ROA setup scripts

- Rename $Host parameter to $DbHost in oracle-functions.ps1 (Invoke-SqlPlus,
  Test-OracleConnection, Get-OracleVersion, Test-PDB, Get-ServiceName)
- Update all function calls in 01-setup-database.ps1 to use -DbHost instead of -Host
- Fix ${Host} -> ${DbHost} in log message (line 147)
- Fix Write-Log "" -> Write-Host "" to avoid empty string parameter error
- Add DbHost/Port parameters and config.ps1 support to setup script
- Update sys-updates/README.md to clarify folder is for future patches only

Tested successfully on ROACENTRAL (10.0.20.130) with Oracle XE 21c.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

proxmox/lxc108-oracle/roa-windows-setup/scripts/lib/oracle-functions.ps1

@@ -131,6 +131,12 @@ function Get-OracleVersion {
         [Parameter(Mandatory = $true)]
         [string]$ServiceName,
 
+        [Parameter(Mandatory = $false)]
+        [string]$DbHost,
+
+        [Parameter(Mandatory = $false)]
+        [int]$Port = 1521,
+
         [Parameter(Mandatory = $false)]
         [string]$Username = "SYSTEM",
 
@@ -149,6 +155,7 @@ EXIT;
 "@
 
     $result = Invoke-SqlPlus -OracleHome $oraHome -ServiceName $ServiceName `
+        -DbHost $DbHost -Port $Port `
         -Username $Username -Password $Password -SqlCommand $sql -Silent
 
     $versionInfo = [PSCustomObject]@{
@@ -201,6 +208,12 @@ function Get-ServiceName {
         [Parameter(Mandatory = $false)]
         [string]$OracleHome,
 
+        [Parameter(Mandatory = $false)]
+        [string]$DbHost,
+
+        [Parameter(Mandatory = $false)]
+        [int]$Port = 1521,
+
         [Parameter(Mandatory = $true)]
         [string]$SystemPassword
     )
@@ -210,6 +223,7 @@ function Get-ServiceName {
     # First try to connect to XE and check if it's CDB
     try {
         $version = Get-OracleVersion -OracleHome $oraHome -ServiceName "XE" `
+            -DbHost $DbHost -Port $Port `
             -Password $SystemPassword -ErrorAction Stop
 
         if ($version.IsCDB) {
@@ -224,6 +238,7 @@ function Get-ServiceName {
         # Try ROA as service name
         try {
             $null = Test-OracleConnection -OracleHome $oraHome -ServiceName "ROA" `
+                -DbHost $DbHost -Port $Port `
                 -Username "SYSTEM" -Password $SystemPassword -ErrorAction Stop
             return "ROA"
         }
@@ -270,6 +285,12 @@ function Test-OracleConnection {
         [Parameter(Mandatory = $true)]
         [string]$ServiceName,
 
+        [Parameter(Mandatory = $false)]
+        [string]$DbHost,
+
+        [Parameter(Mandatory = $false)]
+        [int]$Port = 1521,
+
         [Parameter(Mandatory = $false)]
         [string]$Username = "SYSTEM",
 
@@ -286,6 +307,7 @@ function Test-OracleConnection {
 
     try {
         $result = Invoke-SqlPlus -OracleHome $oraHome -ServiceName $ServiceName `
+            -DbHost $DbHost -Port $Port `
             -Username $Username -Password $Password -SqlCommand $sql -AsSysdba:$AsSysdba -Silent
 
         return $result -match "CONNECTED"
@@ -330,6 +352,12 @@ function Test-PDB {
         [Parameter(Mandatory = $true)]
         [string]$ServiceName,
 
+        [Parameter(Mandatory = $false)]
+        [string]$DbHost,
+
+        [Parameter(Mandatory = $false)]
+        [int]$Port = 1521,
+
         [Parameter(Mandatory = $false)]
         [string]$Username = "SYSTEM",
 
@@ -347,6 +375,7 @@ EXIT;
 "@
 
     $result = Invoke-SqlPlus -OracleHome $oraHome -ServiceName $ServiceName `
+        -DbHost $DbHost -Port $Port `
         -Username $Username -Password $Password -SqlCommand $sql -Silent
 
     $containerInfo = [PSCustomObject]@{
@@ -428,6 +457,12 @@ function Invoke-SqlPlus {
         [Parameter(Mandatory = $true)]
         [string]$ServiceName,
 
+        [Parameter(Mandatory = $false)]
+        [string]$DbHost,
+
+        [Parameter(Mandatory = $false)]
+        [int]$Port = 1521,
+
         [Parameter(Mandatory = $false)]
         [string]$Username = "SYSTEM",
 
@@ -454,9 +489,13 @@ function Invoke-SqlPlus {
         throw "SQL*Plus not found at: $sqlplus"
     }
 
-    # Build connection string
+    # Build connection string (EZConnect format if DbHost is provided)
     $sysdba = if ($AsSysdba) { " as sysdba" } else { "" }
-    $connString = "$Username/`"$Password`"@$ServiceName$sysdba"
+    if ($DbHost) {
+        $connString = "$Username/`"$Password`"@${DbHost}:${Port}/${ServiceName}$sysdba"
+    } else {
+        $connString = "$Username/`"$Password`"@$ServiceName$sysdba"
+    }
 
     $tempFile = $null